IMPROVEMENTS IN APPARATUS FOR COATING GLASS AND OTHER SURFACES WITH GELATINOUS OR VISCOUS PHOTOGRAPHIC COMPOUNDS
Year: 1879

page_text: LETTERS PATENT to Joseph Wilson Swan, of Newcastle upon Tyne, Chemist,
for the Invention of "IMPROVEMENTS IN APPARATUS FOR COATING GLASS AND
OTHER SURFACES WITH GELATINOUS OR VISCOUS PHOTOGRAPHIC COMPOUNDS."
Sealed the 7th May 1880, and dated the 12th November 1879.
PROVISIONAL SPECIFICATION left by the said Joseph Wilson Swan at the
Office of the Commissioners of Patents on the 12th November 1879.
"IMPROVEMENTS IN
JOSEPH WILSON SWAN, of Newcastle upon Tyne, Chemist.
APPARATUS FOR COATING GLASS AND OTHER SURFACES WITH GELATINOUS OR
VISCOUS PHOTOGRAPHIC COMPOUNDS."
The object of my Invention is to effect the coating of plates of glass with the
photographic gelatinous compound commonly known as sensitive gelatine emulsion
by automatic machinery, so as to obtain more perfect regularity in the coating, and
also greater rapidity than by the methods bitherto employed.
I accomplish the object stated by means of a machine consisting of a trough
containing the emulsion, within which a band revolves and carries the emulsion
over the side and below the level of the trough, and there delivers it upon the
plates as they travel in a continuous train upon a band or table beneath it.
I make the trough of earthenware, or of brass, or other metal, plated with
silver, and I jacket it or fit it with a tube or tubes for hot water, with the object of
keeping the emulsion at a suitable working temperature.
The length of the trough must be equal to, or with advantage it may exceed the
breadth of plates to be coated. The depth and width of the trough need not greatly
exceed what is necessary for the accommodation of the lower roller of a system of
rollers, consisting preferably of three or more, around which the band is stretched,
and which carries the band within the trough and brings it into contact with the
surface of the emulsion.
The coating band is formed of india-rubber or other suitable material, and is
stretched upon the system of rollers, preferably one within the trough, one upon its

page_text: front edge, and one beyond this outside the trough and below the level of the
bottom.
I fix the trough above a travelling band or table, upon and by means of which
the train of plates is carried under the coating band. I actuate both the travelling
band for carrying of plates and the coating band by means of a suitable motor, so
that the coating band and the plates move in opposite directions.
By the action of a lever and cam, or other suitable device, I provide for the
tilting up of the trough at the front where the coating band acts, whenever it is
desired to stop coating or to adjust the level of the coating surface. I also place a
reservoir of emulsion near the trough, and connect them by means of a tube.
The reservoir is provided with a gauge tube and a screw for raising or lowering,
so as to maintain the emulsion at a constant level. 1

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Joseph Wilson Swan in the Great Seal Patent Office on the
12th May 1880.
JOSEPH WILSON SWAN, of Newcastle-upon-Tyne, Chemist.
" IMPROVEMENTS IN
APPARATUS FOR COATING GLASS AND OTHER SURFACES WITH GELATINOUS OR
VISCOUS PHOTOGRAPHIC COMPOUNDS."
This Invention relates to "Improvements in Apparatus for Coating Glass and other
Surfaces with Gelatinous or Viscous Photographic Compounds," and has for its object
to effect the coating of plates of glass with the photographic gelatinous compound
commonly known as "sensitive gelatine emulsion" by automatic machinery, so as
not only to obtain more perfect regularity in the coating, but also to effect such
coating with greater rapidity and certainty than has hitherto been practicable.
And in order that my said Invention may be better understood and readily
carried into effect, I will now with the aid of the accompanying Drawings proceed
more particularly to describe the same.
In order to carry my Invention into effect I construct a machine consisting of a
trough containing the emulsion, within which a band, hereafter termed the coating
band, revolves, and to which motion is imparted by means of a system of rollers
over which it is stretched. Such coating band carries the emulsion over the side
and below the level of the trough, and there delivers its charge of emulsion upon the
plates as they travel in a continuous train upon a travelling band or table (hereafter
termed the plate-conveying band) beneath. I so. actuate the coating band and the
plate-conveying band that the coating band and the train of plates upon the plate
conveying-band move in opposite directions.
In the accompanying Drawings, Figure 1 shews a side elevation, Figure 2 an
end elevation, and Figure 3 a plan view of my improved apparatus. A indicates
the trough; B, the coating band; C, the travelling or plate conveying band; D, the
glass to be coated; E and F are levers for tilting the system of rollers over which
the coating band is stretched in order to bring it into contact, or to remove it from
contact, with the plates to be coated.
G, G, are the driving rollers, and H indicates the worm which transmits motion
to such rollers; I is a sheave for driving the machine from any suitable motor, and
J is a weight for keeping the travelling band in the grip of the driving rollers so as
to ensure its travel; K is a pipe communicating with a hot water cistern; L, the
immersing roller; M, the coating roller, and N, the guide roller.
The trough A is made of earthenware, silver, or brass, or any other suitable metal
plated with silver, and is jacketted or fitted with one or more tubes for hot water;
while its length is either equal to or exceeds the width of the line of plates to be
coated. Its depth and width are determined by the requirements of space for the
operation of the immersing roller L, which is formed of wood, or silver, or of brass,
or other suitable metal plated with silver. The coating band B is made of india-
rubber, while the travelling band C is formed either of indiarubber, cloth, linen,
cotton, or any other suitable fabric. The coating roller M is made of india-rubber,
or any other suitable elastic material fixed upon a rigid axle, preferably of iron.
Having thus particularly described and ascertained the nature of my said
Invention and the manner of carrying the same into effect, I would have it
understood that I do not confine myself to the precise details hereinbefore set forth,
as the same may be modified without departing from the principle of my Invention,
which is to effect the coating of glass and other surfaces with gelatinous or viscous
photographic compounds by means of automatic apparatus, so as to obtain a more

page_text: perfect regularity in the coating, and to perform the operation with greater celerity
and certainty.
I claim therefore as my Invention,―
Firstly. The employing automatic apparatus or machinery for coating glass and
other surfaces with gelatinous or viscous photographic compounds, for the purposes
herein before set forth and described.
Secondly. The new or improved apparatus, constructed substantially in the
manner and for the purposes hereinbefore described and illustrated, wherein a
revolving band dipping into a trough containing the emulsion carries a coating of
emulsion over the edge and below the level of the trough, and delivers its charge of
emulsion upon a train of plates carried beneath it by a travelling band or its
equivalent.
Thirdly. I claim the use of a revolving band for applying a coating of sensitive
photographic emulsion to plates of glass and other surfaces, in order to obtain a
more perfect regularity in such coating, and to effect the same with greater rapidity
and certainty.
In witness whereof, I, the said Joseph Wilson Swan, have hereunto set my
hand and seal, this Tenth day of May, in the year of our Lord One thousand
eight hundred and eighty.
JOSEPH WILSON SWAN. (L.S.)