Improvements in or relating to the Manufacture of Moulds or Models.
Year: 1893

page_text: Date of Application, 10th July, 1893-Accepted, 19th Aug., 1893
COMPLETE SPECIFICATION.
Improvements in or relating to the Manufacture of Moulds or
Models.
A communication from GEORGE A. PETERS, M.B., of 171, College Street, Toronto,
County of York, Ontario, Canada.
I, ALFRED JULIUS BOULT, of 323 High Holborn, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
The object of the invention is to provide a simple process by which moulds from
very delicate as well as substantial objects may be accurately produced. It consists
in throwing a spray or fine stream of melted paraffine upon the object or article
from which the mould is to be taken, substantially as hereinafter more particularly
explained.
Figure 1 is a general view of the apparatus by which this process is carried out.
Figure 2 is a sectional enlarged view of this paraffine ejector.
Figure 3 is a sectional enlarged view of the water ejector.
A represents a tank or vessel containing water sufficiently hot to maintain the
paraffine in a liquefied state. Within this a smaller tank B containing the melted
paraffine is placed. Each tank is provided with an outlet tube or spout at or
near the bottom, the inner tank B, being fastened in such a position that the two
outlet tubes are opposite one another.
From the outlet tube of the tank A, a flexible tube C leads to the outer tube of
the ejector D and from the outlet tube of the tank B a smaller tube E running
within the tube C leads to the inner tube of the ejector D. The object of this
device is to surround the tube E conveying the paraffine by a jacket of hot water
so as to maintain it in a liquefied state until it reaches the ejector. The water
passing from the tank A through the jacket to the ejector is allowed to escape
by a waste tube N which is provided with a clamp by which the flow may be
regulated.
F is a reservoir provided with an air-tight valve and supplied with air under
pressure by a pump G or by some other suitable apparatus.
H is a flexible tube leading from the air reservoir F, to the tube O of the
ejector D' by which the air is discharged as a jet through the central opening of
the nozzle 1.
I is an adjustable nozzle connected to the end of the ejector D so that the escape
of the paraffine may be regulated in quantity as desired, or may be entirely checked
if necessary. The adjustment is made by varying the distance of the nozzle I, from
the expanded end of the tube O.
The operation of this invention consists in the application of the above-described
apparatus in the following manner :-
The tank A containing the tank B, is raised so that the paraffine and water
flow by gravitation to the ejector D. By means of the air pump G a moderate
pressure is secured in the air reservoir F and transmitted to the air-tube O, of the
ejector D, causing a stream of air to be ejected through the aperture of the
nozzle I. If the nozzle 1 be now opened the paraffine which should have a melting.
point of about one hundred and twenty-five to one hundred and thirty degrees
Fahrenheit, flows by gravitation from the tube E, and meeting the air jet in the
the nozzle I, is thereby scattered so as to produce a spray which may be made
more or less fine according to the amount of paraffine allowed to escape, and the
force with which the air current is ejected.
The nozzle of the ejector being now directed towards the object of which it is

page_text: desired to obtain a mould, the paraffine is sprayed upon the cool surface upon
which it solidifies instantaneously. In this way the object is covered by a complete
and continuous layer of paraffine which adapts itself to the minutest details of the
exposed surface. After a sufficiently substantial layer of paraffine (say one-
eighth inch in thickness) is thus distributed over the surface, a second factor in
building up the mould is brought into requisition. This consists in a spray of
water produced in a similar way by the ejector J which is connected by the
flexible tube K to the cold water tank L and by the. tube M to the air-
reservoir F..
By causing the spray of paraffine and the spray of water to commingle as they
fall upon the object, it is found that, not only is the solidification and rigidity of
the paraffine favoured, but that globules of water become imprisoned within cells
or capsules of the hardened paraffine, thus assisting in the rapid building up of
the mould.
The object having been completely covered with a mould as thick as the nature
of the object demands, it is found desirable to superimpose a layer of plaster of
paris which strengthens the mould and prevents its warping on removal. While
the plaster of paris is setting, certain silk threads which have been suitably
disposed over the surface of the object before-hand, are withdrawn in such a way
as to cut the mould into such a number of sections that it can be removed with
ease from the object. These sections having been re-adjusted to one another and
cemented by some plaster of paris cream smeared along the lines of union, the
mould is complete.
Before throwing the paraffine upon the object or article to be moulded, it is
advisable to take measures for the easy removal of the mould by smearing the
object with oil, rubbing it with soap or spraying it with albolene, as may be required
by its nature or texture.
Throwing paraffine in the form of spray upon the object to be moulded,
produces the best result, but this object may be secured in a measure by permitting
the paraffine to flow upon the object in a fine stream.
Having now particularly described and ascertained the nature of this said inven-
tion, as communicated to me by my foreign correspondent and in what manner the
same is to be performed, I declare that what I claim is :-
1. An improved process for making a mould of an object or article by the
throwing of a spray or fine stream of liquefied paraffine upon the object or article
from which the mould is to be taken, substantially as and for the purpose specified.
2. The within described apparatus for making the mould of an object or article
consisting of an ejector connected by a tube to an elevated tank of melted paraffine
in combination with a tube connected to a reservoir of air under pressure and
with the ejector substantially as and for the purpose specified.
3. The within described apparatus for making a mould of an object or article
containing an ejector connected by a tube to an elevated tank of melted paraffine
a hot water tank within which the paraffine tank is placed, a tube leading from
the hot water tank and surrounding the tube through which the paraffine passes in
combination with a tube connected to a reservoir of air under pressure and with
the ejector substantially as and for the purpose specified.
4. The within described apparatus for making a mould of an object or article
consisting of a paraffine ejector arranged as described in combination with an
ejector connected to a water tank and to a reservoir of air under pressure substan-
tially as and for the purpose specified.
Dated this 23rd day of June 1802
W. P. THOMPSON & BOULT,
Agents for the Applicant.