IMPROVEMENTS IN MOULDING OR SHAPING METALS
Year: 1854

page_text: LETTERS PATENT to Robert Maclaren, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVEMENTS IN
MOULDING OR SHAPING METALS."
Sealed the 8th March 1854, and dated the 12th January 1854.
PROVISIONAL SPECIFICATION left by the said Robert Maclaren at the
Office of the Commissioners of Patents, with his Petition, on the 12th
January 1854.
I, ROBERT MACLAREN, of Glasgow, in the County of Lanark, North Britain,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN MOULDING OR SHAPING METALS" to be as follows:-
This Invention relates to the production of the necessary compressed state
of the sand or loam used in the formation of the mould, or the securing the
effectual moulding action at one operation, and by means of great pressure
applied in the following manner:-The mould box may be of the usual form,
with cross bars for holding the sand or loam together, but the bottom is in a.
separate loose piece just fitting within the sides of the box, and the bars do
not reach the lower edge of the sides, so that the bottom may be raised to a
limited extent. inside the box. The lower mould box is placed in a high
hydrostatic press and is filled with sand or loam, and the pattern is then
placed in position. The upper mould box is then placed above the lower
one, and is likewise filled with sand or loam. This upper box is also
formed with a false bottom and in a similar manner to the lower one but

page_text: it is placed in a reversed position in reference thereto. The upper box is
secured in any convenient manner to the resisting head of the press, and
the boxes may be conveniently filled from a sand hopper placed at the top
of the press. The hydrostatic pressure is then applied, and is made to act
entirely between the false top and bottom of the mould box, and produces
a degree of compression proportionate to the extent to which the top and
bottom are driven in, whilst the sand or loam is forced with an equal pressure
on both sides of the pattern. When the pressure has been given and the
moulding force is released, the upper or reverse mould is hooked or suspended
from the fixed framing, so that as the pressing movement returns, the upper
or reversed mould is left behind. This uncovers the pattern or core, which is
then removed by the continued back traverse in a similar way, and the
completed inould can then be at once run off to its destination.
This method of forming moulds is more particularly applicable to patterns
of slight depth and to such patterns as are in the form of castings, having the
patterns in one piece on a flat plate. It is obvious that the compressing power
employed according to this Invention may be derived from a screw or other
mechanical movement, the pressure being given up or down or at any other
angle. The Invention is further applicable to the making of loam or sand
cores for metal pipes and similar articles.
In this case the core mould is made in two or more pieces in such a
manner as when submitted to the requisite pressure they may close together
and form the required shape of core, without allowing any of the sand or loam
to escape.
This system of moulding is particularly suited for working on the principle
of the plans already patented by Messrs. Fairbairn, Hetherington, and Dug-
dale, and the working action is derivable from various sources other than those
which have been herein-before referred to, such as steam cylinders, or direct
steam or air pressure lever movements, rack and pinions or rollers, and instead
of working or pressing upon one box at a time, it is proposed, in certain cases,
amature to want was town we mana havas

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of January, in the year of our Lord One
thousand eight hundred and fifty-four, in the seventeenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Robert Maclaren, Her special license that I, the said Robert Maclaren, my
executors, administrators, and assigns, or such others as I, the said Robert
Maclaren, my executors, administrators, or assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN MOULDING OR
SHAPING METALS," upon the condition (amongst others) that I, the said Robert
Maclaren, by an instrument in writing under hand and seal, should par-
ticularly describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Maclaren, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement;
reference being had to the accompanying Drawings, and to the letters and
figures marked thereon, that is to say :-
My said Invention relates to the production of the necessary compressed
state of the sand or loam used in the formation of the mould, or the security
the effectual moulding action at one operation, and by means of great pressure
applied in the following manner:-The mould box may be of the usual form
with cross bars for holding the sand or loam together, but the bottom is in a
separate loose piece just fitting within the sides of the box, and the bars do not
reach the lower edge of the sides, so that the bottom may be raised to a
limited extent inside the box. The lower mould box is placed in a hydrostatic
press and is filled with sand or loam, and the pattern is then placed in position.
The upper mould box is then placed above the lower one, and is likewise filled
with sand or loam. This upper box is also formed with a false bottom and in
similar manner to the lower one, but is placed in a reversed position in refe-
rence thereto. The boxes being filled with sand, which may be conveniently
effected from a sand hopper placed at the top of the press, the hydrostatic
pressure is applied and is made to act entirely between the false top and
bottom of the mould box, and produces a degree of compression proportionate
to the extent to which the top and bottom are driven in, whilst the sand or

page_text: loam is forced with an equal pressure on both sides of the pattern. When the
pressure has been given and the moulding force is released, the upper or
reverse mould is hooked or suspended from the fixed framing, so that as
the pressing movement returns, the upper or reverse mould is left behind.
This uncovers the pattern or core, which is then removed by the con-
tinued back traverse in a similar way, and the completed mould can then
be at once run off to its destination. This method of forming moulds is
more particularly applicable to patterns of slight depth and to such pat
terns as are in the form of castings having the patterns in one piece on a
flat plate. It is obvious that the compressing power employed according to
this Invention may be derived from a screw or other mechanical movement,
the pressure being given up or down, or at any other angle. The Invention is
further applicable to the making of loam or sand cores for metal pipes and
similar articles. In this case the core mould is made in two or more pieces in
such a manner, as when submitted to the requisite pressure, they may close
together and form the required shape of core, without allowing any of the sand
or loam to escape. Instead of working or pressing upon one box at a time, it
is proposed, in certain cases, to cause one pressure apparatus to work upon two
or more boxes. And although I have herein-before referred to the treatment
of a complete mould, that is to say, both sides of a mould at once, it will be
obvious to the practical moulder that the halves or any other portions of a
mould or moulds may be treated separately. This system of moulding is par-
ticularly suited for working on the principle of the plans already patented by
by Messrs. Fairbairn, Hetherington, Dugdale, and Jobson; and the working
action is derivable from various sources other than those which have been
herein-before referred to, such as steam cylinders, or direct steam or air pres-
sure, lever movements, rack and pinions, or rollers.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the several explanatory Figures on the Sheet of
Drawings hereunto attached.
Figure 1 on the Sheet of Drawings is a front elevation of a hydrostatic
pressure as arranged for compressing moulds according to my Invention; and
Figure 2 is a corresponding side elevation. In these two Figures the mould
box is represented in position, as ready to receive the compressing action.
Figure 3, on the Sheet of Drawings, is a vertical section of a mould box as
constructed to suit the purposes of my Invention; and Figure 4 is a plan of
the same, but with the pattern removed; these two Figures being drawn to a
larger scale. Figure 5, which is drawn to a still larger scale, is a vertical
-section of the contrivance I employ for forming the gate in the mould for the

page_text: entrance of the molten metal.. The details of the hydrostatic press may be
varied in many ways, but the form represented in the Drawings differs very
little from that of an ordinary press. The pressure cylinder A is sunk into the
flooring, and is furnished in the usual manner with the lower cross head or base
frame casting B. This is connected by the two strong tensiou rods C with the
upper resisting cross head D. The press represented is of a sufficient size for
compressing three moulds of the size of that represented. The ram E is
furnished with the large pressure table F, upon which the mould boxes are
placed. The mould box consists of upper and lower portions G, H, the
pattern plate I being placed between them. I have herein-before mentioned
that internal cross bars may be made in the mould box, but the box repre-
sented is shewn without them as I find they are but seldom required, although
they may be used with advantage for some particular kinds of patterns. The
upper mould box G is an open rectangular casting, having flanges J formed upon
its sides for the purpose of suspending it in the press, in the manner to be
herein-after described. The box G has also formed upon it the usual perforated
lugs K for connecting it with the lower box H, by means of similar lugs fitted
with pins, and both boxes have projections L at the ends for lifting them by.
The lower portion of the mould box is in two pieces H, H', forming a rectan-
gular box into which a loose false bottom M is fitted. This false bottom is
cast with lugs N, which project through slots formed in the sides of the lowest
portion of the mould box, and arranged to admit of a short vertical
traverse of the false bottom M. This false bottom rests upon a casting O,
which answers as a plunger for forcing the false bottom up the interior of the
mould box, so as to compress the sand contained in the latter. The bottom
box H, has four supporting legs P bolted to it near the corners, and these
legs pass through holes in the table F; and rest upon adjustable screw pins Q,
carried by a fixed entablature or frame R below the table F. In proceeding
to treat a mould by this apparatus the table F is brought down to the level
represented in the Drawings, and the mould box H, H¹, being then placed
upon it, the legs P resting upon the pins Qwill support the mould box at such
a height above the table that the false bottom M will descend to its lowest
position, or that represented in the Drawings, whilst the plunger O will just
reach the surface of the table. The lower portion H, H', of the mould box
being filled with sand, the pattern plate I with the pattern on. it is placed in
position, and the upper mould box G is placed on the top of the pattern and is
also filled with sand. Then on the ram E rising and carrying up the table F,
the whole will rise clear of the pins Q, and as soon as the resisting action
comes into operation above, the hydrostatic pressure will force the plunger O,

page_text: and false bottom M, up inside the mould box, thereby forcibly compressing
the sand, and producing a very sharply defined mould of the pattern I.
The sand in the upper mould box G is acted upon by a plunger S,
bolted to the resisting cross head D, and fitting as a false top within the
mould box, the rising of which, whilst the plunger is stationary, causes the
compression of the sand. The cross head D is cast so as to form a hopper
to contain the sand for forming the mould, and the sand is fed to the mould
boxes by a sluice door T, in the face of the plunger S. A large hopper of
wood or other material may be built upon the top of the cross head D, so as
to contain a sufficient supply of sand for a considerable number of moulds.
The plunger S carries a pair of short bracket arms U on each side, to which
are jointed the link pieces V, formed with catches for supporting the upper
mould box by means of the flanges J already mentioned, and also for sup-
porting the pattern plate I, which projects on either side of the mould box for
that purpose. When the compression of the sand has been effected, the ram
is caused to re-descend, the upper mould box G, and pattern I, being left
suspended to the catch links V, so that the lower portion of the mould can be
removed. In taking away the lower portion of the mould, the upper portion A
of the box is lifted off the bottom portion H', by the lugs N, of the false bottom
M, which false bottom will have been forced up to the upper portion H of
the box. The box H, H', may in some cases be made in one piece, or bolted
together, but I generally prefer to have it in two pieces, as represented. Or
instead of removing the upper and lower portions G, H, of the mould sepa-
rately from the press, the upper mould G, and pattern I, may be left sus-
pended as described, the lower mould H being caused to descend a short space.
The pattern I is then taken from between the two moulds, and the ram is
caused to re-ascend and carry the lower mould H up again to the mould G,
so as to close the two ready for the casting operation, in which state they may
be removed together from the press, or in case of very large castings, the
casting operation may be performed with the mould still in the press. In
order to form the gate or entrance in the mould for the molten metal, I
insert into the pattern at the point where the gate is to be, the piece W,
Figure 5, and on the plunger S, I fix the tubular piece X, directly above
the piece W. The tubular piece X is provided with a joint Y, which
enters a cavity in the top of the piece W, a spring Z in the tubular piece
✗ pressing the point Y outwards. On the mould box and pattern, with the
gate piece W rising against the plunger S, the gate piece W enters the tubular
piece X, and so prevents the breakage of the parts which would result with
a rigid gate piece if the moul box were raised too high against the plunger S,

page_text: and a perfect gate or entrance will always be formed in the mould, whatever
within certain limits may be the depth of the sand after compression. In
the Drawings I have only represented one complete mould box as placed in
the press for treatment, but the press as delineated is adapted for compressing
three moulds at once, and presses may be constructed so as to be capable of
compressing a greater or less number of moulds if required. In compressing
moulds of articles, the different parts of which vary considerably in depth, I
make the acting surfaces of the top and bottom plungers of shapes approach-
ing to the general outline of the pattern so as to obtain a more uniform
compression of the sand. And in cases where the mould is of considerable
depth, the sand or loam is filled in in layers, and each layer is compressed
before the addition of a subsequent one, so as to make the mould of a more
uniform density.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I may observe, in conclusion, that I do not confine or
restrict myself to the precise details or arrangements which I have had occasion
to describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of my Invention; but what I
consider to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent, is,-
First, the general arrangement and construction of machinery, apparatus, or
means to be employed in moulding or shaping metals, as herein-before
described.
Second, the system or mode of producing the requisite degree of compression
in the sand loam or other material of which moulds for casting metals are com-
posed, at one or more operations by the application of great pressure exerted
over the entire mass of material of the mould or section of mould under treat-
ment, as herein-before described.
In witness whereof, I, the said Robert Maclaren, have hereunto set my
hand and seal, this Tenth day of July, in the year of our Lord One
thousand eight hundred and fifty-four.
ROBERT MACLAREN. (L.S.)