Improvements in Developing, Toning, and Fixing Apparatus for Photographs.
Year: 1897

page_text: Date of Application, 17th Aug., 1897-Accepted, 12th Mar., 1898
COMPLETE SPECIFICATION.
Improvements in Developing, Toning, and Fixing Apparatus for
Photographs.
I, ARTHUR SCHWARZ, of Berlin, Schoneberg, Germany, Manager of Works, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
-
My invention relates to an apparatus for developing, toning and fixing photo-
graphs in large quantities.
In the apparatus hitherto used, the feeding of the moist paper through the
several baths presented the disadvantage, that special feeding mechanism is required
which increases the cost of the plant as well as the working expenses, as owing to
their operation in the several solutions such feeding mechanism is exposed to great
wear.
I have devised an apparatus whereby the feeding mechanism operating in the
baths is dispensed with and to this end I have provided my developing apparatus
with peculiar feed rolls of a simple and cheap construction.
My invention is illustrated in the annexed drawing forming a part of this
specification and wherein;
Fig. 1 shows an elevation of the new feed roll.
Fig. 2 shows a transverse section of same.
Fig. 3 shows a longitudinal section of the apparatus, provided with the new feed
rolls.
Fig. 4 shows a transverse section of one of the baths on an enlarged scale; and
Fig. 5 shows an end view of the feed roll on the same scale.
As shown in Fig. 1 the roll A is provided over its entire length with grooves a
and the roll is not cylindrical but is slightly tapering toward the centre from both
ends. These rolls will hold the paper when it reaches same from the bath with a
slightly lateral pull sufficiently strong to prevent the formation of folds, without
injuring the paper.
As the roll A has a larger diameter towards the ends than in the centre and the
whole roll turns uniformly, the ends have a larger periphereal speed than the centre
so that they exert a certain pull on the corresponding sections of the paper. As the
diameter becomes smaller toward the centre, the periphereal speed also decreases
and is smallest. in the centre. The pull on the sections of the paper varies in
accordance therewith, and consequently the paper is advanced by the rolls absolutely
without any folds being formed.
These rolls are mounted above each bath as shown in Fig. 3, and the exposed
paper 6 drawn from the reel B over the roll C into bath 1 and after passing through
same is conveyed by the feed roll A into bath 2 and so on until it is fed through the
entire series of bath 1 to 12 by the propulsion of the feed rolls A and carried off
over a roll X. The loops of paper hanging down into the baths are weighted down
by means of small rolls D the journals of which are housed in longitudinal slots d
Fig. 4 provided in the side walls of the baths, so that the length of the loop of
paper in the bath may be changed at will.

page_text: The feed rolls A are rotated with equal speed by a common shaft 6 preferably
by the medium of a worm c¹ and worm gear f, so that the strip of paper is fed
without any guiding device through the baths, and is only weighted down by the
small rolls I so as to obtain a perfect immersion in each bath.
It is obvious that the rolls D merely rotate and are not subjected to any strain
whatever. Consequently they can be made of a material not affected by the liquids
and solutions in the several baths.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed I declare that what I
claim is:-
1. An apparatus for developing photographs consisting of a series of baths
containing the required solutions longitudinally grooved rolls rotating at the same
speed being arranged over each bath, substantially as herein described and shown.
2.In an apparatus of the class described a longitudinally grooved feed roll
decreasing in diameter toward the centre from both sides substantially as herein
described and shown.