IMPROVE- MENTS IN COMPOSITE MOULDS FOR MOULDING PLASTIC ARTICLES
Year: 1885

page_text: I SAMUEL BOURNE FURNIVAL of Stoke-on-Trent in the County of Stafford
Manufacturer do hereby declare the nature of the said invention for "IMPROVE-
MENTS IN COMPOSITE MOULDS FOR MOULDING PLASTIC ARTICLES" and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement to be as follows that is to say:-
This invention has for its object improvements in composite moulds for moulding
plastic articles which are so constructed as to be true in register and to bear a
greater pressure without injury than those in present use with less cost in fitting
together.
In order that my invention may be clearly understood and more easily carried
into practical effect I have appended hereunto a sheet of drawings upon which is
illustrated a pair of moulds which shews the principle of construction sufficiently
clearly to enable those acquainted with the trade or similar trades to construct
them both for this and similar purposes though the little details may require
slight alteration to suit any particular purpose. The mould is shown round but
may be made of any desired shape to suit the article to be moulded.
Figure 1. is a sectional elevation through the lower moulds on line K. L.
Figure 2. is a plan of the bottom mould plate or frame before the plaster is run
in to form the mould proper.
Upon a foundation plate A which may be either solid or annular or otherwise
lightened out I either cast in one with it or separately from it the ring B to form
a thoroughly substantial and stout tension ring for the purpose of effectively
resisting the tendency of the plaster or other plastic material or substance C which
forms the mould proper from cracking or expanding or otherwise altering in shape
under heavy pressure which has been the fault of the old mould in use before the
date of my previous Patent, No 3000 of the 7th March 1885. No doubt the
ring B when cast one with the circular or other plate A as shown upon the
drawing is best as the one part tends to stiffen the other. The legs or bearing
points & may be made in any desired shape such for instance as the examples
shown by d square, e round, fannular or h attached to the side or cast one with
the ring B. In either or any case it is only necessary to level the tops of legs as
for instance e¹ and f¹. There may be two three four or more legs to each mould

page_text: according to the shape and size. The dowels may be the usual loose pieces 8 and 8¹
fixed in the face of the plaster or mould proper as these work well enough for
keeping the mould from moving laterally or I may use the guides in the legs as set
forth in my previous Patent herein before mentioned. The upper mould M may
be formed in an exactly similar manner to that explained for the lower one when
the pressure is great and such is necessary but in many cases the plain plate and
lega shown would be sufficient without the flange B. It will be thus understood
that my metal frame gives great stability to the mould proper and the legs a
perfectly true surface and limit to the pressure with but very little fitting. The
mould proper may be otherwise formed in the usual way or as set forth in my
previous Patent before mentioned.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare what
I claim is
The improvements in composite moulds for moulding plastic articles of the
plate A and ring B with bearing or sustaining surfaced points such as d, e, f, or h
or their equivalents substantially as and for the purpose herein set forth.