IMPROVEMENTS IN THE MANUFACTURE OF CAST TUBES OF GOLD, SILVER, COPPER, ZINC BRONZE, AND OTHER METAL
Year: 1882

page_text: LETTERS PATENT to Thomas Morgan, Secretary, Inventors Patentright
Association Limited, of 21 Cockspur Street Charing Cross in the County of
Middlesex, Patent Agent, for an Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF CAST TUBES OF GOLD, SILVER, COPPER, ZINC BRONZE, AND
OTHER METAL," communicated to him from abroad by Eugène Isidore
Levavasseur of Paris in the Republic of France, Manufacturer,
i
PROVISIONAL SPECIFICATION left by the said Thomas Morgan at the
Office of the Commissioners of Patents on the 20th November 1882.
THOMAS MORGAN, Secretary Inventors Patentright Association Limited of
21 Cockspur Street Charing Cross in the County of Middlesex, Patent Agent
" IMPROVEMENTS IN THE MANUFACTURE OF CAST TUBES OF GOLD, SILVER,
COPPER, ZINC BRONZE, AND OTHER METALS" (a communication to me from abroad
by Eugène Isidore Levavasseur of Paris in the Republic of France, Manufacturer
The tubes of precious metal employed in the manufacture of jewellery have
hitherto been obtained with considerable difficulty by means of successive striking
and drawing; this method moreover has the disadvantage of only enabling the
tubes to be made in short lengths.-On the other hand, tubes produced by the
usual processes of casting are not suited for being employed in jewellery.
This Invention relates to a process of manufacturing cast tubes, which presents.
the advantage of producing tubes of perfectly constant and uniform thickness
without any solution of continuity throughout the entire length of the tubes.-The
machine for performing the operation of casting is furnished with a movable or
travelling mould, provided throughout its entire length with a longitudinal slot or
casting gate, and enclosing a fixed or rigid core or mandril which determines the
internal dimensions of the tube. This fixed core is supported at one extremity by
the mould, and at the other extremity fits into a tube fixed to the frame of the
machine, and upon which the travelling or movable mould slides.
The arrangement of the machine consists mainly as follows:-
A cast iron frame supports a travelling mould formed by two flasks presenting
sami circular bollame

page_text: These two flasks are connected together by bolts having thumb nuts, and slide in
a slotted bed plate cast in one with the frame of the machine.-A rack extends
along the whole length of the under part of the flasks, and gears with a pinion on a
shaft rotated by a pulley.-Inside the mould is a metal core corresponding to the
internal diameter of the tube that is to be cast.-This core is supported at one end,
and travels with the mould.-The other end of the core is supported in a tube
attached to a bracket or support on the frame of the machine. The diameter of
the tube is equal to that of the annular space in the mould, and consequently
corresponds to the external diameter of the article to be moulded.-A crucible
holder is attached to the frame and supports a crucible which is tilted automatically
by a cord connected at one end to the extremity of the driving shaft and at the
other end to a lever connected to the crucible holder.
The action is as follows:-
The crucible being filled with molten metal, the mould is set back to the
beginning of its stroke that is to say, its end touches the support of the tube
hereinbefore referred to.-When the machine is set in motion, the mould is moved
longitudinally by the rotation of the pinion gearing with the rack.-The cord is
wound upon the end of the shaft, and tilts the crucible, the melted metal flowing
into the gate of the travelling mould. This metal, on entering the annular space
between the mould and the core, is supported on one side by the extremity of the
tube, and on the other side by the end of the mould, and in proportion as the
mould travels longitudinally away from the said tube, the metal spreads around
the core along the entire length of the mould.-When the cast tube is complete
the mould is removed-from-the machine the thumb nuts are unscrewed from the
bolts, and the tube may then be taken out. This system-of-casting is applicable
to tubes of any metal and of any size, it being simply necessary in order to cast
tubes of different sizes to change the mould and its core, together with the guide
tube. With a view to facilitating the withdrawal of the internal mandril or core
from the tube after the operation of casting, a special machine is employed.
This machine is constructed with a sliding bar or plate, presenting a raised
surface or table, upon which a certain length of the tube is placed.-Above this bar
or sliding plate is arranged a stationary plate, which can be moved upwards or
downwards in the frame of the machine by means of screws, which carry worm
wheels, engaging with endless screws connected to a shaft which is turned by
means of a hand wheel.-By these means the plate may be moved down so that it
touches the tube resting on a traveller.-Motion is imparted to the latter by the
intervention of a connecting rod worked by a crank on a transverse shaft, receiving
motion by suitable gear from a shaft, which is actuated by suitable driving pulleys.
-The longitudinal motion of the traveller or sliding table has the effect of
separating the tube from the mandril, so as to enable the latter to be drawn out
without difficulty.-This result is obtained by the rolling action to which the tube
is exposed between the raised surface on the traveller and the underside of the
stationary plate.-When the tube arrives at the ends of the said raised surface, it
drops out and can thus be shifted longitudinally for a distance corresponding to the
extent of surface rolled, until the whole of the tube has been submitted to the
rolling action of the machine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by.
the said Thomas Morgan in the Great Seal Patent Office on the 19th May
1883.
THOMAS MORGAN, Secretary, Inventors Patentright Association Limited, of
21 Cockspur Street Charing Cross in the County of Middlesex, Patent Agent,
"IMPROVEMENTS IN THE MANUFACTURE OF CAST TUBES OF GOLD, SILVER, COPPER;
ZINC BRONZE, AND OTHER METALS" (a communication to me from abroad by Eugene
Isidor Levavasseur, of Paris in the Republic of France, Manufacturer)
The tubes of precious metal employed in the manufacture of jewellery have
hitherto been laboriously produced by means of successive hammering or stamping
and drawing, and the tubes thus obtained are necessarily of very limited length.-
The ordinary processes of casting tubes are not capable of being applied to the
casting of these tubes for jewellery.
According to this Invention, these tubes are manufactured with molten metal,
with the advantage that they present a strictly uniform and regular thickness
without any break or solution of continuity throughout the entire length of the
tube.
An essential part of the machine constructed according to this Invention for
performing the operation of manufacture consists of a movable mould, provided
with a slot acting as a casting gate extending throughout its entire length.-This
mould also contains a stationary core, which determines the internal diameter of
the tube. The core supported at one extremity in the mould is guided at the
opposite extremity by a tube fixed to the frame, and upon which the movable
mould slides.
The construction and action of the machine will be readily understood by means
of the following description with reference to the drawing hereunto annexed-
Fig. 1 is an elevation partly in section
Fig. 2 is a plan, and Fig. 3 is a transverse section of the improved machine
for casting tubes.
The cast iron frame A supports the movable mould, which is formed by two
flasks B, presenting semicircular hollows a; these two flasks are connected by
bolts having wing nuts C and are supported by a guide D, cast on the frame A.
Rack E extends along the entire length of the under side of the flasks, and engages
with a pinion I on a shaft J, worked by a pulley K.-The mould contains a metal
core F, corresponding to the internal diameter of the tube that is to be produced.
This core is supported at one extremity at b, and remains fixed to the mould.
The other extremity of the core F is supported by a tube H, carried by a
support G.-The external diameter of the tube H is equal to that of the cavity of
the mould, and is consequently equal to the external diameter of the tube that is to
be made. A crucible holder L is carried by the frame A, and supports an oscillating
or balanced crucible M, operated automatically by a cord N, one extremity of which
is wound upon the end of a driving shaft J.-This crucible contains the molten
metal, and before commencing operations, the mould is placed in position to
commence its travel, that is to say, is brought into contact with the support G-
The machine being then set in motion, the mould travels forward under the
action of the pinion I, gearing with the rack E-The cord N is wound upon the end
of the shaft J, and tilts the crucible so that the molten metal is poured into the
channel on the movable mould. The metal is supported on the left by the
extremity of the tube H, and fills the cavity surrounding the core F as the mould
travels forward, until this cavity or space is completely filled throughout the whole
length of the mould.-When the tube is completed, the mould is removed from the
machine the nuts C of the bolts are unscrewed, and the cast tube extracted.―
This process is applicable to the casting of tubes of any dimensions and of any
metal. For this purpose it is only necessary to change the mould the core and
he tubular guide H

page_text: The machine illustrated in front view in Fig. 4, in end elevation in Fig. 5 and in
plan in Fig. 6, is employed to facilitate the extraction of the core or mandril from
the interior of the tube after the casting operation. This machine is provided
with a slider O, having a table e, upon which a certain length of the tubing is
laid Above this sliding plate is provided a fixed plate P, capable of being raised
or lowered on the frame G by means of screws R₁ R¹ R₁ R₁ carrying worm
wheels d d d d in gear with endless screws e. e. fast on the shaft R, which is
turned by means of a wheel S'-The plate P is thus brought down until it touchies
the tube resting upon the sliding plate O.-The latter is set in motion by a rod S,
worked by a crank T on the shaft U, which is driven by the shaft V and the
transmission or gearing x-The horizontal or sideways motion of the plate O has
the effect of loosening the tube on the mandril, so as to enable the latter to be
readily extracted-The rolling is effected upon the surface x. x; when the tube
arrives at the extremities x, it falls out, and may then be moved forward for a
distance equal to the length rolled, and so on until the whole of the tube has passed
through the machine.
In the machine described, the tube is cast between the sides of a movable
mould and a stationary core contained in the mould, but it is found that in certain
cases, the fixed core inside the mould and the guiding tube may be dispensed with
by merely providing on the frame a fixed stem or bar, which enters the mould in
such a manner that the tube may be cast inside the mould as the latter travels,
and remain adhering to the sides of the mould without an internal support or
core The inconvenience of having to extract the core from the mould according to
the preceding arrangement-is-thus-obviated.-
This modified form of the machine is represented in Fig. 7 of the accompanying
drawing. The support G carries a bar H, which enters the mould B.-This bar,
which completely fills the cavity of the mould, terminates in a head F of fire clay,
fixed by a screwed rod a-As the mould travels, the tube is cast round the head-F
of the bar, and remains applied to the sides of the mould, as shown in the
drawing; the operation of extracting the tube from the mould is then performed
with the greatest ease.
Having now particularly described and ascertained the nature of the said
Invention, and in what manner the same is to be performed or carried out in
practice I claim the bereinbefore described system of manufacturing cast tubes
of any length of gold, silver, copper, zinc, bronze, or other metal, and in particular,
(1stly) a casting machine comprising the combination of a mould containing a
fixed core with a guide tube fixed to the frame, this mould travelling horizontally
under the lip of the crucible, which delivers the molten metal in such a manner
that the latter progressively fills the cavity formed around the core.
(2nd) The machine for rolling the tubes issuing with the mandrils from the
casting machine, for the purpose of detaching the said tubes from the mandrils, in
order that the latter may be readily extracted, the tube being exposed to a rolling
action between two surfaces suitably drawn together, one of such surfaces being
stationary and the other partaking of an alternating lateral or horizontal motion.
(3rd) The machine for casting tubes without a stationary core, by simply
providing the frame with a fixed bar, which enters the mould, so that as the mould
travels the tube is cast, and remains adhering to the sides of the mou'd without
the support of an internal core.
In Witness whereof I the said Thomas Morgan have hereunto set my hand
and seal this nineteenth day of May in the year of our Lord one thousand
eight hundred and eighty three.
THO. MORGAN
L.S.)