IMPROVEMENTS in PhotograpHIC EXCHANGE BOXES WITH SLEEVE FOR PREVENTING THE PENETRATION OF LIGHT TO THE PLATES
Year: 1884

page_text: COMPLETE SPECIFICATION.
I HEINRICH KAYSER, Doctor of Philosophy and Lecturer at the University in
Berlin of N° 16° Neue Wilhelm Strasse in the City of Berlin and German Empire
do hereby declare the nature of my Invention for IMPROVEMENTS in PhotograpHIC
EXCHANGE BOXES WITH SLEEVE FOR PREVENTING THE PENETRATION OF LIGHT
TO THE PLATES 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 the construction of photographic exchange boxes the
object of which is to permit the removal of the exposed plates and to bring a fresh
plate in its place in full daylight without being compelled as heretofore to slide
the box or case into a second case in order to be able to effect the said manipulation
id. est. the exchange of a fresh plate for the exposed plate.
By employing my construction of exchange boxes I am able to exchange B
series of 12 to 15 plates when glass plates are employed and expose them
consecutively.
The front or foremost plate lies just behind the slide in suitable position for
exposing and is after being exposed withdrawn and placed behind the other plates
which have not been exposed. For this purpose one end of the box or case is
made to act as a door so that the exchange can be readily effected by inserting
the hand, as however the plates must be entirely withdrawn from the box or case
and it is necessary to exclude the light I employ a sleeve of suitable material
capable of excluding the light, which is slid or pushed over the arm of the operator.
A suitably arranged spring or springs, presses or press against the moveable
partition or false bottom of the box or case and hold the serie of plates firmly
against each other when the outer or foremost plate is to be exposed whereas a
device is provided so that the pressure of the spring can be removed and so that
the plates rest loosely against each other and can be readily exchanged.
The accompanying Drawings represent my improved exchange box or case in
section.
A is the slide for closing the box or case behind which the plates B which aro to
be exposed are arranged so that they rest against the frame of the box or case.
The single plates are separated by an intermediate layer of black or other paper
through which the light cannot penetrate which said layer is loosely attached to
the back of each plate. The plates B are continuously pressed against the bearing
ID: 11

page_text: surface of the frame by means of a suitable spring acting on the moveable or falso
bottom so that the front or foremost plate is kept in focus.
I represents the side of the box or case which is formed to act as a door, which
said door lies snugly against the two ledges or rails K and L and is moveably
connected with the box or case by means of a piece or strip of canvas, leather or
other suitable material which is glued or otherwise attached to the box or case
frame and clamped tight by means of the ledge K or a suitable joint, hinge or
hinges can be employed to the like purpose.
The ledges K. L serve also to hold the sleeve O of suitable fabric which will
exclude the light, which said sleeve can be folded up and carried in the space M of
the box or case between the door I and the outer door N to the exchange box or
case which said door is provided with suitable hinge or hinges I. The requisito
play for enabling the plates to be readily exchanged is attained by drawing back
the false bottom or partition C towards the bottom of the said box or case thereby
compressing the spring or springs D which can be effected by connecting a rod or
spindle E to the false bottom C whichi said rod E is provided with a suitable
knuckle or other joint F and reaches through the bottom G of the box or case.
The outer end of the rod E is provided with a ring H so that by pulling this ring
outwards the joint F is drawn to the outside of the box or case, the spring D
compressed and space or play for the exchange of the plates in the said exchange
box attained, whereby the false bottom C can be retained in the position mentioned
above by simply giving the outer end of the rod E a partial revolution of 45°
around the knuckle or other joint so that the said outer end of the rod E lies flush
.or about flush with the bottom or back of the box or case.
As soon as the exchange of the plates has been effected the rod E is returned to
its original straight position by means of the ring H whereupon the plates aro
again firmly compressed by the intervention of the false bottom C and the
spring D. My improved exchange box or case for photographic plates possesses in
comparison with the ordinary exchange boxes not only the advantage of the
.enormous reduction in weight but also of being able to employ plates of various
sizes for which purpose it is only necessary to insert a suitable adjustable or
readily removable ledge to lessen the length or width of the said box or case but
so as to leave the space. next the door I, free. My said improved box or case can
.be employed for the ordinary dry plates "but is specially adapted for dry plates in
.which the emulsion is not attached to glass but to a thin flexible plate of suitable
material such as have already been the subject of various patents.
The photographic exchange box as shown in the accompanying drawing can
contain about 50 of such said flexible plates and when such said plates are about
.18 centimetro wide and 24 centimetres long, weighs inclusive of the plates only
about 4 lbs.
The back or bottom of the case is also provided with suitable hinges to facilitate
the introduction of the plates into the box.
Having now 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. The construction of a photographic exchange box or case in which the plates
can be changed in full daylight by employing a suitable sleeve O of a fabric which
will not permit the light to penetrate the same thus rendering the employment of
an extra case unnecessary whereby the said box or case consists of the bottom or
back Garranged to open on suitable hinges, the slide A, the moveable false bottom
or partition C which said false bottom and with it the plates are pressed forward
by means of a suitable spring or springs D so that the plate to be exposed is pressed
snugly against its seat in the frame, and of the door I formed in the one end or side
of the said box or case substantially as described and shown in the accompanying
Drawings.
"
2. The moveable fulse bottom C is provided with a rod E which said rod has
a knuckle or other joint F at about the centre of its length and a ring H or its
equivalent at the outer end so that when the ring H to the said rod is pulled

page_text: outwards the rod E is drawn out through a boring in the back or bottom of the
box or case, the spring or springs D is or are compressed, the false bottom drawn
back and the plates given free so that the exchange can be made for which purpose
the rod E is turned on its knuckle or other joint F and the false bottom held in
its rear position whereby the arın of the operator must be inserted in the said
sleeve O of impenetrable material or fabric substantially as described in foregoing
Specification and shown in the accompanying Drawings.
3. The combination of the door N to the space at the end of the box or case to
receive the sleeve O with the said sleeve of light excluding fabric O and the door I
to the inner space of the said box or case substantially as described in the foregoing
Specification and shown in the accompanying Drawings.
4. The general arrangement and construction of the parts of my improved
photographic exchange box or case substantially as and for the purpose set forth
in the foregoing Specification and shown in the accompanying Drawings.
Dated this 24th day of March 1884.