Improvements in and connected with Photographic Cameras, and Tripod Stands therefor.
Year: 1896

page_text: Date of Application, 1st June, 1896-Accepted, 1st June. 1897
COMPLETE SPECIFICATION.
Improvements in and connected with Photographic Cameras, and
Tripod Stands therefor.
We, ALFRED EUGEN DEHNERT Manufacturer and KARL HEINRICH
GOTTFRIED HEDWIG, Mechanician, both of No. 3 Grindelberg, Hamburg, in the
Empire of Germany 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 relates to an apparatus for photographic purposes which,
although of very small size, allows of changing any desired number of plates,
whilst the folding stand or tripod is adapted to be stored in the interior of the
apparatus.
The apparatus is illustrated in the accompanying drawings in which-
Figure 1 is a longitudinal vertical section through a camera when arranged for
low or wide plates, and having the objective underneath the finding lense.
Figure 2 is a longitudinal vertical section through a camera when arranged for
high or narrow plates, and having the objective and finding lense side by side.
Figure 3 is a plan of the magazine for high plates, or it is also an elevation of
the magazine for wide plates.
Figure 4 is another view in elevation of the magazine.
Figure 5 is a front part sectional elevation on an enlarged scale from the
point downwards of the time shutter shown in Figure 1 and the mechanism
shown in plan on Figures 8 and 9, the ground line in Figure 5 being X' Y.
Figure 6 shows the same with the time shutter closed and in the reverse position
from that shown on Figure 5.
Figure 7 is a side elevation of Figures 5 and 6.
Figures 8 and 9 illustrate details of the camera.
Figure 1 shows one leg of the stand in the folded condition.
Figure 11 shows the same ready for use, and
Figures 12 and 13 show the plate-counter.
A camera constructed in accordance with this invention differs from those
heretofore in use, in that a single movement only is necessary to effect the
changing of the plates, to operate the instantaneous and the time shutters, and to
count the plates that have been exposed.
Similar mechanism is used for either high or low plate cameras so that similar
letters are used throughout the following description.
The apparatus consists of two parts, i.e. the removable or exchangeable plate
magazine which holds 24 plates, and which can be changed for a fresh magazine
when the aforesaid plates have been used up; and the camera proper, which latter
again is divided into two compartiments, i.e. the camera B with the objective C
with the instantaneous time shutter D (Figure 1), and the compartment E with the
two finding mirrors, and in which space the stand can be packed for transport.
When the plate magazine has been affixed to the apparatus, and the slide a
(Figure 1) has been pushed over the magazine to attach it to the camera, the
magazine slide b is pushed back so as to expose the first plate situated nearest to
the objective. When photographs are being taken, then the operation is as follows;
The lever c shown on Figures 5, 6, 7, 8, and 9 is at this moment in the position

page_text: shown on Figure 8 and it is rotated on its spindle by means of the outside
lever and thumb catch through one-third of a revolution to the right hand,
during which movement the studs d, d, fixed to said lever move into the position 3, 3,
the lever operating the time shutter D in a manner hereinafter described, then
further rotation takes the toothed segment e round with the lever c and causes the
toothed wheelf engaging with e to rotate once about its axis. This causes the
crank g fixed thereto to make one revolution also, and to carry the connecting rod n
(Figure 1) counerted thereto during the half revolution to its furthest point to the
rear. By this means the lever is moved from the position to a (shown in
dotted lines on Figure 1) during half a revolution of the crank g; also rotating the
pinto which it is attached, that pin / having keyed upon it the toothed wheel m
as shown on Figures 3 and 4.
Meanwhile the toothed wheel m (Figures 3 and 4) mounted on the pin, makes a
third of a revolution about its axis in the direction of the arrow, whilst the pinion
fixed upon the shaft a is rotated, carrying with it the two pinions o o fixed upon
either side which in turn move the toothed bars or racks p p from one part of the
magazine to the other. The racks p move by means of the spring catches (shown
clearly on Figure 4) the exposed plate out of the part A of the magazine into the
part A', while simultaneously the racks p' move by means of the spring catches q¹
an unexposed plate out of the magazine A¹ into the magazine A. Then the lever c
(Figure 8) which has up till now only moved through a sixth part of a circle, is
turned entirely over to the right, so that the crank g describes the second half of
the circle, but is again situated in its original place, and brings the lever i
(Figure 1) back into its old place. The toothed wheels o (Figures 3 and 4)
which now rotate in the opposite direction to that of the arrow, to the extent of
one third a revolution about their axis 8, move the racks p and pl into their
original positions the springs g and q being thereby pressed back by the next
following plates into the racks, so that they slide past the same, until they have
returned into their original positions, the catches on the springs and then
taking behind the next following plates. The arrangement is such that the two
springs and acting upon the flat surface of the plates always press them back
into their original positions until all the 24 plates have been exposed, that is to say,
have travelled in a circle from one magazino through the other.
By affixing a fresh magazine, it is possible to take an unlimited number of
photographs without the necessity of having to use the dark chamber.
The plates are contained in sheet metal Trames which are simply inserted when
the lid (Figures 1 and 2) has been removed.
tt (Figures 1 and 2) are mirrors which serve for the purpose of focussing the
picture to be photographed in the size required by the plate, that is to say, for a
high narrow plate or for a low wide plate.
The image (Figures 1 and 2) is produced upon the dull or ground glass plate o
by means of the finding lens aand of the finding mirror t.
To close the finder (which is illustrated in its open condition in Figures 1 and 2)
the lid w which is kept open by the spring is shut, and is fastened by means of
the slide y; the toothed bar or rack z fixed to the lid acting to rotate the small
toothed wheel F in the direction of the arrow. This small toothed wheel is also
capable of rotating together with a small wheel G which is situated behind the
same and which is coupled to a pitch chain H and is guided by three small
wheels J K K. The mirror t is fastened to the pitch chain so that when the
finder lid w is closed, the mirror is drawn up close under the duli plate. When
the finder lid is again disengaged from the slide y, the pitch chain is moved by the
rack by means of the small toothed wheels F and G in the direction opposite to
that of the arrow (Figures 1 and 2) and it carries the mirror t with it downwards
until the mirror is at an inclination of 45° to the dull plate, and stops in this
position. The rack moves in a guideway L during the motion of the finder lid.
The instantaneous and time shutter D (Figures 5 6 and 7) consists of two
segments N and N of sheet steel, adapted to rotate about the two pivots or

page_text: axes O and O'; further, of the base piece P which is situated on the bottom of
the camera and upon which the spring Q and the cylinder R are mounted.
The slide M shown on Figure 5 and 6 acts as a locking bar the bar being in the
locked position in Figure 5 and in the released position in Figure 6.
When a picture is to be taken, the slide M (Fig. 5) is pushed completely into
the camera (Figure 6) the gap M' in its length allowing the upward travel of the
shutter mechanism as hereinafter described, while the outside lever a and thumb
catch are operated as hereinbefore described.
The lever (Figure 8) thus rotates in the direction of the arrow, whereby the
said lever acts by means of the pin el on the small lever 10 and pulls the releasing
cord S that passes over the sinall wheels S S S S and thus to release the
cylinder R froin the pin T (Figures 5 and 6) which held the said cylinder. The
latter is now caused by the pressure of the spring Q to shoot up and carry up with
it the bracket piece U. On the latter is a spring V which forces by means of the
tongue W the two points X and Y of the steel segments so far apart as to completely
uncover the objective aperture though if the gap M in the releasing position
the tongue could not move up and operate the segments. Then as the cylinder
and the bracket piece continue their movement, the steel stud Z forces the two
projections 1 and 2 of the sheet metal plates (which are directed towards each
other) apart and closes the shutter again. But meanwhile the lever e (Figure 8)
has moved the pins d d fixed thereto as far as the points 33, whereby the operations
of changing the plates now ensue as hereinbefore described. When the pins d
have reached this point, they carry the toothed segment e round with them, and
thus move the toothed wheel f. The latter is connected to a shaft 4 (Figures 5, 6,
and 7) having a cranked portion 5 situated underneath the crank g which is
rotated together with the said shaft once around the axis. When the crank 5 has
moved through half its course, the cord 6 which passes over the small wheels 6' 6'
63 64 65 and is connected to the tension lever 7, is pulled or tightened to such an
extent as to cause thereby the cylinder R to be pressed back into its original
position by means of the lever 7, whilst the pin T is caused by the spring 8 to take
again into the upper part of the cylinder, so that the latter is set or cocked for a
fresh exposure.
Then the crank 5 now completes its course through the second half of the circle.
The spring 9 pulls the lever ; the crank 5 moves again into its original position,
and the pulling cord d is pulled tight, back into its old position by the action of
the spring 9 and lever 7 on the slack cord.
When a fresh exposure is to be effected, the lever e which is now in the position
shown in Figure 9, is rotated in the direction of the arrow. The movement of the
parts actuated thereby is the same as hereinbefore described; only that it takes
place in the opposite direction; and the pin e' moves the lever 10 with it, whereby
the cord S is pulled tight, the cylinder R is disengaged from the pin T (Figures 5
and 6) and the cylinder, shooting up by the spring pressure, makes a fresh exposure.
When the pins d situated on the lever c reached the places 11, the further rotation
of the lever C, moves the toothed segment e with them, whereby the shutter is
again set or cucked, and a plate is changed in the manner and by the mechanism
hereinbefore described. The screw 12 (Figures 5 6 and 7) serves to regulate the
velocity of the instantaneous obturation. When the screw is moved right out, the
shutter obturates with the least velocity, whilst the more the screw is screwed in,
the more the base P compresses the spring Q, and the quicker is the obturation.
Figure 10 shows one of the three legs of the tripod stand in a folded state.
13 and 14 are pins that take into the outer wall of the camera. The tripod is
placed and stored in its folded state in the space E (Figures 1 and 2). When the
tripod is used, the several joints or sections 15 (Figure 11) which are provided
with springs, are opened out, and a stay or fastening 16 is provided for the purpose
of increasing the strength and rigidity of the leg.
The plate-counter chown in Figure 12 is controlled by the axle 4 (Figures 5
and 6) and the crank 9 (Figures 5, 6, 8 and 9). At the upper end of the axle 4

page_text: there is provided a pin 17 (Figures 5 and 12) which serves when the axle 4 is
rotated to press down the lever piece 18 (that is fixed at 19 and carries a spring 23)
to such an extent as to cause the pawl 20 to carry round one tooth further the
toothed wheel 22 it being firmly held at each tooth by the detent pawl 21. Then
the lever piece 18 together with the pawl 20 is pressed by the spring 23 back again
against the axle 4, because the latter makes only one revolution about its own axis at
each exposure; thus the toothed wheel 22 advances each time through the distance
of one tooth. This toothed wheel has 24 teeth and is rigidly connected to a
pointer adapted to move over a scale so that at each exposure the said pointer
indicates how many plates have been exposed.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. A photographic camera for receiving any desired number of plates, comprising
a removable or exchangeable plate magazine consisting of two chambers (A A¹)
also a lever c (Figure 8) arranged on the outside wall of the casing, said lever
serving by means of multiple translation or transmission of its motion, to convey
the plate, which has been exposed, into the store or magazine A, and at the same
time to convey an unexposed plate into the chamber A whilst springs (9 g¹ and r¹)
act to press the plates together and to grip them at their edges substantially as
hereinbefore described.
2. A form of construction of the camera specified in Claim 1, in which by
rotating a single lever c (Figure 8) the plates are changed, the instantaneous and
time shutter (which is adapted to be regulated from outside by means of spring
pressure Q Figure 5, and of an adjusting or set screw 12, Figure 5 6 and 7) is
operated, and the device for counting and indicating the number of plates that have
already been exposed, is set in operation.
3. In a camera as specified in Claim 1 the construction of the finding mirrors E
Figures 1 and 2, the arrangement being such that with only one finding lens u and
by means of the mirrors, the picture to be photographed is shown of the same size
as the photograph twice, i.e., as a high narrow image and as a low wide image
in each case on a separate dull or ground glass plate."
4. In a camera as specified in Claim 1, the arrangement of the compartment for
the finding mirrors E, Figures 1 and 2, such that the specially constructed folding
legs of the tripod or stand (15 Figures 10 and 11) can be stored in said compartment
for or during transport.
Hated th 1900
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.