Improved Photographic Camera with Plate Exchanging Device.
Year: 1891

page_text: Date of Application, 24th July, 1891-Accepted, 29th Aug., 1891
COMPLETE SPECIFICATION.
Improved Photographic Camera with Plate Exchanging Device.
I, RUDOLF STIRN of Berlin in the German Empire, 34, Sebastianstrasse,
Manufacturer, 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 a photographic camera in which the exchange or transfer
of the plates is so effected, that the plates arranged close behind each other in a
partitioned off chamber can be singly removed for exposure and can then be
returned to the same or any other desired part of the partitioned chamber, the
camera having as many partitions or spaces as plates can be contained in the
same.
The plate exchange is effected by means of a case or sheath advantageously of
sheet metal or other suitable material of a size corresponding to the size of the
plates employed, said sheath being so arranged on the upper outer surface of the
camera that the same can make a part revolution, advantageously about 90° and is
so constructed that when the said sheath is placed in vertical position or nearly
so, the interior of the same will communicate with one of the partitioned off spaces
of the plate chamber whereas when the same is turned as abovementioned about 90°
this communication will be shut off. The lid of the camera being arranged to slide
in appropriate guide ways I am enabled to successively remove the unexposed
plates from the plate chamber by inverting or turning the camera topsy turvy 80
that the desired plate falls into the aforenamed sheath whereupon the said sheath
is given about a quarter revolution on its axis and the sliding lid closed, so that the
slot beneath the sheath stands over the exposition chamber. The sheath is now
again turned so as to stand erect and thus allow the plate to fall into the
exposition chamber of the camera. It is only necessary to reverse the order of
the foregoing operations to remove the exposed plate and transfer the same back to
the same partitioned space in the chamber from which it was taken.
It will be obvious from the foregoing that all the plates in the chamber can be
exchanged by simply sliding the lid or cover and placing the sheath in an erect or
a laying position and inverting the camera.
In order to facilitate the aforementioned operations the case of the camera is
provided with a scale or index along which a pointer attached to the lid glides so
that any one of the plates can be removed from its partitioned space and returned
to the same after having been exposed etc. The camera is furthermore so arranged
that each movement of the lid or cover will place the spring of the shutter to the
object glass or lense under tension and will also denote by a counting disc to which
partition space the lid or cover is to be adjusted for taking a fresh plate.
Instead of full partitions, ledges can be used for dividing the chamber and
preventing the plates from coming in contact with each other. In order to make
my invention more clear I refer to the accompanying drawing in which similar
letters denote like parts in all the views.
Fig. 1 is a side elevation of the camera with partly removed side wall showing
the pawl for rotating the counting disc.
Fig. 2 is a central vertical section through the camera.
Fig. 3 is a plan or top view of the camera partly in section.
Fig. 4 is an end elevation of the camera with the plate removed to show the
automatic shutter device.
Fig. 5 is a section on the linea in Fig. 4.
Fig. 6 is a detail view of the spring for holding the plate to be exposed, in

page_text: My improved camera consists of two compartments a separated from each other
by an opaque partition b, of which the forward compartment, closed on all sides,
forms the exposing chamber and the rear compartment, which is open at the upper
end, the plate chamber.
The side walls of the plate chamber are provided with a number of ledges or thin
partitions c so as to subdivide the chamber into the desired number of partitions in
order that the plates lay one behind the other without coming in contact with each
other and may be inserted in or removed singly from the plate chamber.
The exchange of the plates d, i.e. the transfer of a non-exposed plate from the
plate chamber into the exposing chamber in front of the partition d and back again
into the plate chamber, is effected by the sliding lid or cover e and the hollow light
tight sheath fattached to the same, the cylindrical part f¹ of the said sheath being
arranged to turn in a socket g and thus make a part revolution of about 90° in order
that the hollow space of the sheath may be made to correspond with the slot e' in
the cover e when the said sheath is in erect position but out of communication with
said slot as soon as said sheath is turned down onto the lid.
When the sheath (Fig. 2) is placed erect, the hollow space of the same will, by
means of the slot e¹ in the lid e, when suitably adjusted, be brought into com-
munication with any desired partitioned space of the plate chamber so that by
inverting the camera the plate d in the said space will fall into the hollow case or
sheath f. If the sheath fis now turned down onto the lid e and the latter moved so
far forward that the slot e' comes over the slot in front of the partition b, and the
sheath is again placed in an erect position, the camera reinverted or brought back
to its original position and the plate to be exposed allowed to drop into the exposing
chamber of the camera.
When the exposition is completed the plate can be transported back into the
same division of the plate chamber by operating the parts in like manner as afore-
named but of course in opposite direction i.e. out of the exposing chamber into the
division of the plate chamber from whence it was originally taken.
Now in order to adjust the lid e for removing a plate from a certain division of
the plate chamber, a pointer g¹ is attached to the same said pointer being arranged
to glide along a scale h on the guide way i for the lid e.
The zero mark on the scale denotes the position the lid or cover must occupy in
order to allow a plate to fall out of the sheath through the slot el into the
exposing chamber and vice versa whilst the Figs. 1, 2 etc. denote the number of the
divided off space or division of the plate chamber from which, when the lid e is thus
placed, a plate can be abstracted or into which the exposed plate can be inserted.
In order to indicate the number of plates which have been exposed a rotary
indicator disc k can be arranged in or on the camera said disc being toothed on its
periphery or provided with a ratchet wheel and laterally with figures which can be
made visible through an opening in one of the walls of the camera said figures
corresponding with the number of the plate divisions in the plate chamber.
A spring pawl is attached to the lid advantageously in such manner that each
time the lid or cover is moved forwards to take a plate from the plate chamber for
exposition the indicator disc k will be rotated a distance equal to the distance
between two figures on said disc k thus showing plainly to which division the plate
is to be returned after exposure and from which division a fresh plate should be
taken.
In order to attain an exact adjustment of the plated to be exposed in the
exposing chamber, the partition b carries two leaf springs m n arranged so as to
gear one above the other (Figs. 2-6) and to press against the plate d in order to
hold the same so firmly against appropriate stops or their equivalents that all
movement of said plate in operating the camera is absolutely precluded.
When it is desired to remove the plate after being exposed, the pressure of the
springs m n can be removed by employing a sliding rod o or other suitable device
for pressing the said springs inwards against a suitable stop m' of the upper spring m
so as to bring the lower spring into the position represented by the dotted lines in

page_text: Fig. 2 thus relieving the plate d from pressure in order that the same can be
readily exchanged.
An essential feature of the improved camera is also the device for automatically
putting the spring to the shutter to the object glass or lense under tension when the
lide is operated.
This object is attained by means of a rod p arranged vertically in the fittings to
the case of the camera and abutting at its lower end against an excentrically located
pin g of the shutter r so that when the rod p is depressed by means of the knob the
shutter r will be closed and the spring to the same put under tension and held in
this position until released by means of the lever s. This shutter arrangement can
be adapted to moment and also for all other kinds of photographing. The head of
the rod p which projects into the way over which the sliding lid or cover e passes is
bevelled as shown at pl so that the fitting t of the lid e can operate on the same
both fitting and lid being grooved so that when the shutter is operated the rod p
can rise. This device has the advantage that a renewed exposure of the plate
cannot take place as the shutter spring will only then be put under tension when
the exposed plate has been returned to its division or divided off space in the plate
chamber and a fresh plate inserted in the exposing chamber.
Having now particularly described and ascertained the nature of my said inven-
tion and the manner in which the same is to be performed, I declare that what 1
claim and desire to secure by Letters Patent is :—
1. A photographic camera in which the exchange of the plates from the sub-
divided or partitioned off plate chamber to the exposition chamber and back again
to the plate chamber is so effected by means of the sliding lid or cover e that the
plates to be exchanged are fed into light tight sheath attached to the said lid or
cover and arranged to be given a partial revolution the shifting of which when
operating the sliding lide enables the plates to be transferred from the plate
chamber to the exposing chamber and from the exposing chamber back again into
the desired space of the partitioned or subdivided plate chamber substantially as
described.
2. In photographic cameras with sliding lids and transfer sheaths spring under
tension in operating the lids or cover e by means of the rod p substantially as
described.
3. In photographic cameras with sliding lids and transfer sheaths the application
of a scale such as to the case and a pointer to the lid of the camera for
adjusting the parts and a counter disc k operated in moving the sliding lid
substantially as and for the purpose set forth in the foregoing Specification and
shown in the accompanying drawings.
4. In photographic cameras with sliding lids and transfer sheaths, the application
of springs such as m, n for securely holding the plate during exposure the latter
being released from the pressure of the springs by operating a sliding rod such as o
substantially as specified.
5. The general construction and arrangement of the parts in my improved
photographic camera substantially as specified.
Dated this 24th day of July 1891.