Improvements in the Method of Producing Coloured Glass Lights for Lenses, also applicable for other suitable purposes.
Year: 1896

page_text: Date of Application, 17th July. 1896
Complete Specification Left, 15th Feb., 1897-Accepted, 3rd Apr., 1897
PROVISIONAL SPECIFICATION.
Improvements in the Method of Producing Coloured Glass Lights
for Lenses, also applicable for other suitable purposes.
We JOSEPH DAVIS of 14, Edward Street, West Bromwich in the County of
Stafford Manager of Glass Works and ARTHUR JAMES DAVIS of 1. Birmingham
Road in the aforesaid Town and County Artist in Stained Glass, do hereby declare
the nature of this invention to be as follows:
This invention relates more particularly to the manufacture of ruby, green, or
white glass lenses and diaoptric lights used for ships, lighthouses, coast lights and
for railways, signal boxes, trainways and the like or for wheeled vehicles generally
where the same may apply.
In the production especially of ruby coloured glass for the above named or
other purposes it has hitherto been not only an expensive process but the result
thereby obtained has not been found completely satisfactory added to which a very
considerable amount of labour in the various processes needed has had to be gone
through thus involving additional cost.
Our improvements consist in the employment of flat pieces of glass of ruby, or
green, or white according to requirements cut to the desired size and shape circular
or otherwise.
To produce say, a ruby lens we take a suitable concave iron mould and place
the flat piece of ruby glass upon the top of same which is heated to the required
degree so that it may bend into the shape of the mould, we then fill the bent
glass lining with molten glass metal which is already prepared, and press the same
down with a plunger or with a press made of iron or other hard substance_so
that the molten glass metal amalgamates with the ruby glass in the mould.
then pass the mould and its contents into a kiln heated for the purpose, afterwards
it is taken out and the glass contents reinoved and ground and polished in the
parts requiring to be so treated. It may be stated that the surface of the lens so
formed will not be affected in any way by contact with the mould and will not
require grinding and polishing which is an important factor, in cost.
By our improved process a far better, clearer, and more regular degree of colour is
given to the lens thus produced than has been possible by hitherto known means,
moreover we can make them of a much larger diameter say 18 inches or more which
has hitherto not been practicable and at a minimum cost. Numerous other advantages
will be found to exist by our invention as the lights reflected through the glass lenses
can be seen at much greater distance which is a most important point for ships lights,
lighthouses, const lights, and railways and signals, etc., which will be obvious.
Other tints of glass than ruby, green, or white may be produced in a precisely
similar manner to that described but we have mentioned particularly ruby, green or
white inasmuch as they form the requirements for the above uses and the difficulty
experienced in obtaining a perfectly even ruby tint is chiefly what we have sought to
overcome.
EDWD. J. PAYNE & SON,
Warwick Chambers, 104, Colmore Row, Birmingham,
Patent Agents for the Applicants.

page_text: affected in any way by contact with the bed of the mould.
Tourea
glass being upon the face of the planó-convex lens the refractive power of the same
is greatly increased as the colour is evenly distributed throughout the lens when seen
from the face or the sides.
Referring to our improved process for the production of the dioptric lenses
somewhat similar means are employed. The mould is formed, in its bed of the
configuration of the face of the dioptric lens.
Figure 5. represents in sectional elevation the iron mould shewing the mass of molten
white metal and
Figure 6. represents a special construction of iron curved combiner and compresser
in connection with the mould as hereinafter described.
Figure 7. represents in sectional view the dioptric lens taken on line A. B. smaller
scale drawing Figure 9.
Figure 8. represents a perspective view of the dioptric lens.
Figure 9. is a perspective front view of same. In the several figures the thick black
lines represent the coloured glass.
A sheet of coloured glass B. is heated and bent upon the convex heated
combiner and compresser E. the coloured glass is retained in place upon the same
by suitable flange pieces or clips F. while white molten metal C. is placed in a
mould A. of the form required for the outside face of the dioptric lens. The coloured
glass plate B. is then pressed by means of the said combiner and compresser E. and
press or plunger D. on to the molten mass C. which is thus evenly distributed in the
bed A of the mould A. and the coloured and white metals are amalgamated or
combined and form the solid dioptric lens. We then with a suitable tool take hold of
the already made dioptric lens and place it in the fire to polish the surface; afterwards
we place it in the kiln to anneal.
In the process of making these lenses a number of coloured glass plates may be
previously bent and kept heated at the necessary temperature required so as to be in
readiness for placing on the convex under face of the heated combiner and compresser.
This curved combiner and compresser forms an important part of our improved
process in-as-much as a uniform temperature is maintained in the coloured face or film
whilst moulding the dioptric lens thus ensuring the perfectly even distribution and
combination of the inner coloured face or film to the white body whereby a uniform
colour is obtained.
The inner coloured face or film being of a denser specific gravity than the white
glass of the body of the lens it is the means of strengthening the same, thus
preserving the true form.
Lenses produced in the manner and by the means described possess numerous
advantages, as, being much clearer in colour than those hitherto made, it will be
obvious that the lights refracted through same are capable of being seen at a much
greater distance which is a most important point for signalling and such like
purposes.
Other colours for the lenses than those above described may be produced in a
precisely similar manner, the difficulty, especially in obtaining a perfectly even ruby,
is what we have chiefly sought to overcome.
Referring to the other articles named we can apply our method such for instance
in the manufacture of certain kinds of table glass such as round oval or square glass
dishes or stands or for other like or analogous purposes in which case by the use of
suitably shaped moulds and combiners or compressers we shall be able to combine
with the white glass a coloured glass lining or facing on the inside surface, the
process for this purpose will be carried out in a similar manner to that described with
reference to the dioptric lenses.
We are aware that plain or plano-convex lenses and dioptric lenses have been
made of plain and coloured glass in various ways and by other methods, and we
therefore do not claim broadly the said combination except in connection with our
improved process and in combination with the means herein described for producing
the said lenses, but we are not aware that the other articles such as table glass,