Improvements in Apparatus for Copying or Transferring Photographs.
Year: 1896

page_text: Date of Application, 25th Nov., 1896-Accepted, 25th Nov., 1897
[Communicated from abroad by the "NEUE PHOTOGRAPHISCHE GESELLSCHAFT," of
Berlin-Schöneberg, in the German Empire:]
Improvements in Apparatus for Copying or Transferring
Photographs.
I GUSTAVE ADOLPHE DE KATOw of 93 & 94 Chancery Lane in the County of
London England Engineer and Patent Expert. 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 :-
This invention has for its object to prevent the production of blunt edges in
copying or transferring photographs automatically. Such edges could not be hitherto
avoided in the processes used wherein the paper was pressed by means of a padded
plate against the negative fixed to the glass plate of the copying frame. It has
moreover always been a particularly difficult task to produce sharply outlined copies
when several negatives had to be copied at the same time as the different negatives
have seldom the same thickness and a padded plate is not sufficiently elastic to
overcome such irregularities. This defect moreover, cannot be remedied by increasing
the pressure as the fragility of the glass plate sets a limit thereto.
This invention has for its object a pneumatic apparatus for copying or transferring
photographs and the like, whereby the above mentioned defects are fully obviated.
This improved copying apparatus is shown in two working positions in Figs. 1 and 2
Sheet 1 of the accompanying two sheets of drawings, Sheet 2 being a diagrammatic
view of the whole arrangement lighted by electricity.
Upon the framework of the machine is fixed a pneumatic copying frame consisting
of the frame enclosing the glass pane S, of the india rubber sheet D, the moveable
plate or table 0 and the negative or negatives N. Between the india rubber sheet D
and the negative or negatives N is fed in any suitable manner the endless paper
strip P, while powerful spiral springs F fixed to the said framework press the plate O
against the glass pane S. The india-rubber sheet however is not under pressure
throughout its surface, only its edges are caused to adhere tightly owing to their
being provided with india rubber strips L which are pressed against similar strips B
placed on the glass pane S to correspond with the india rubber strips L, thus forming
an air tight enclosure of the hollow space surrounded by the strips L in the parts
where the paper strip P enters the apparatus.
Close to these edges and within the tightning strips L india rubber tubes G are
provided, being connected to an air exhausting apparatus H (Sheet 2), so that by
exhausting the air from the hollow space between the india rubber plate and the
glass pane the negative and the paper strip can be firmly pressed against such pane,
and it matters not whether one (Fig. 1) or several negatives (Fig. 2) are placed under
the latter. As, however, before a vacuum is made, adhesion is already produced in
consequence of the pressure on the strips B and L exerted by the springs F, it is not
necessary to make so thorough, a vacuum as to expose thereby the glass plate to
be broken.

page_text: This apparatus being designed for quick successive operations, the paper band P
is accordingly, when properly illuminated, fed forward after each exposure, and
the plate is promptly moved away from the glass pane S, while the impression,
the adhesiveness and the formation of a vacuum follow quickly on.
To be able to carry on these successive steps of the process in quick and correct
order, the sinking, lifting and tightening of the plate must be effected by rotating
mechanism of special construction, which opens and closes at the proper time, the
air exhausting conduit. But as the impression of the india rubber sheet must follow
during this rapid process, the vacuum required therefor is not made directly but
indirectly by the air pump in such a manner that the latter acts constantly on a
receiver whence starts the air conduit H provided with a cock C (Sheet 2) and to
which are fixed behind this cock, the different india-rubber air pipes G which pass
through the plate O and terminate close to the india rubber plate D immediately
behind the glass pane S. The table or plate O is pressed by springs and the
impression is taken off by means of a cam E fixed to the driving shaft W¹ which is
constantly in motion. Upon this shaft is mounted a toothed wheel which imparts,
with the aid of intermediate gear V a rotary motion to a second shaft W2 carrying
likewise a cam T-which actuates, at the right moment a double armed lever h fixed
upon the cock C, this lever h being held in constant contact with the cam T by means
of the spring K. During the period of exposure the moveable part of the apparatus
assumes the position shown in Fig. 1. The plate O is held under pressure by the
springs F, the shaft W and the gear actuated thereby are rotating as well as the two
cams E and T. During this rotation the cam E strikes with its projecting point n
.the roller R which is fixed to the sliding bar Z, surrounds the shaft W¹ and carries
the plate O, thus depressing the roller K, the bar Z and the plate O until the roller
comes to bear against the circular part of the cam. The lowering of the table causes
the cock C to be closed and as the cam T rotates at the same time as the cam E, its
projecting side edge moves the lever h fixed to the shell of the said cock in its closed
position by overcoming the tension of the spring K. The plate O with the india-
rubber sheet D fixed thereon is depressed the cock C is closed and the paper strip
can be fed through the apparatus and under the negative or negativen in any suitable
.manner so that a sufficient length of unexposed paper comes upon the india rubber
sheet D Fig. 2. Meanwhile the rotation of the shaft W¹ not being interrupted, the
cams E and T continue to rotate and as during such rotation, the roll R and the end.
of the lever h bear on the concentric curve of the cams E and T, .the plate O
maintained in its lowered and the cock in its closed position (Fig. 2). As soon
however as a new paper strip comes upon the plate O, the roller R and the lever n
having reached the extreme edge n¹ of the cams E and T, the former together with
the end of the lever h lose their support in consequence of the continuing rotation
of the cams and the springs F coming into action raise the plate 0, while the
spring K opens the cock C. This action is so timed that the cock is opened
immediately that the plate () is under pressure and the tightening strips B L. have
closed the edges of the india rubber plate. At this moment a vacuum is formed in
the hollow space between the india rubber sheet and the paper strip by the receiver
which is not shown in the drawings (Fig. 2). The hollow space is sufficiently freed
from air at one stroke to cause the firm adhesion of the india-rubber sheet
throughout its surface and the exposure follows until the cam E in its
uninterrupted rotary course depresses again the roller R and thus while closing
the cock lowers the plate 0.
Thus during one revolution of the shaft, the plate O is depressed while the cock in
the air conduit is closed; a fresh length of paper is fed into the apparatus; the
plate O is raised and subjected to pressure, the cock in the air conduit is opened and
a vacuum is formed in the apparatus, and lastly the paper is exposed to the light for
a given time, whereupon the above steps are repeated in the same order.
The illumination of the sensitized paper can be obtained from natural light but I
prefer using electric lighting and accordingly I arrange a bell jar I (Sheet 2) secured
to the frame A and placed over the glass plate S, this jar being provided with a

page_text: suitable number of electric lamps. As the sensitized paper is fed forward it should
not be exposed to the light and hence the electric lamps are extinguished while the
table or plate O is depressed, being re-lighted when the paper is receiving an
impression from the negative or negatives. For this purpose the wires b b from the
electric lamps are connected to contact springs a a bearing against the shaft W2 or a
disc mounted on the latter and connected with the electric circuit in such a manner
that at the moment when the air conduit H is opened in consequence of the rotation
of the shaft W2 and the india-rubber sheet firmly presses the sensitized paper
against the negative or negatives the current is flowing and hence the lighting takes
place.
This current will continue to flow on so long as the cock C is open, but so soon as
it is closed the shaft W2 has turned so far that the contact is broken and hence the
light is extinguished.
As the sensitized paper is fed forward, while the table O is lowered and the cock
is closed, this feeding motion will take place in the dark, exactly as it was
intended to do.
Instead of connecting the electric contrivance for the electric lamps with the gear
actuating the cock H, it may be similarly connected with the mechanism used for
raising and lowering the table O.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that
what I claim is:
1. A copying or transferring apparatus provided with a pneumatic pressure pad
wherein the plate or table O carrying the resilient bearing (the india rubber sheet D)
is subjected to pressure by spring power while on the contrary it is drawn off by
a pull mechanism Z R alternately actuated by the shaft of the machine in such a
manner that when the plate is in its uppermost position and pressure is applied, a
device closing the air conduit of an exhausting pump is automatically opened, this
device being closed again automatically when this table is lowered substantially as
herein described and shown.
2. In the copying or transferring apparatus above claimed the arrangement of a
receiver in the air conduit for the purpose of rapidly producing the exhaustion of the
copying arrangement, substantially as herein described and shown.
3. In the copying or transferring apparatus above claimed, the arrangement of
adhesive strips B on the glass plate to thoroughly tighten the edges, when pressure
is exerted on the table or plate ().
4. In the copying or transferring apparatus above claimed, the electric lighting
arrangement consisting of a glass bell jar or cover I placed on the glass plate S of
the apparatus, wherein the electric wires are connected with the mechanism for
opening and closing the vacuum conduit or with that for raising and lowering the
table or plate O in such a manner that the electric lighting takes place when the
sensitized paper is impressed but is extinguished when the said paper is merely fed
forward, substantially as herein described and shown.
Dated this 14th day of November 1896.