Improvements in or connected with Photographic Shutters.
Year: 1894

page_text: Date of Application, 4th Sept., 1894
Complete Specification Left, 8th Sept., 1894-Accepted, 27th Oct., 1894
PROVISIONAL SPECIFICATION.
Improvements in or connected with Photographic Shutters.
We, WALTER OEHMKE, of 35, Dorotheenstrasse, Berlin, Mechanic, and CARL
PAUL GOERZ, of 140, Hauptstrasse, Schöneberg, near Berlin, Manufacturer, both
in the Empire of Germany, do hereby declare the nature of this invention to be as
follows:-
Our invention relates to a photographic instantaneous blind shutter, in which the
slit in the blind is capable of being narrowed or widened by means of a knob placed
outside the apparatus, according as it is desired to give a longer or a shorter
exposure.
The blind is made in two portions stretched upon rollers and, when the shutter is
being set, the blind is wound onto one of the rollers and at the same time, a spring
situated in the other roller is placed in tension. The exposure is effected by
releasing a catch-lever when the blind is drawn by the spring on to the roller.
The two portions of the blind are connected together by cords which are wound
upon drums mounted loose upon the spindle of the spring roller and having fixed
thereto toothed wheels which engage with pinions situated on a spindle. A spiral
spring presses against one of the drums and constantly tends to force this drum
towards the roller so as to cause a pin upon the roller to engage in a hole in a
toothed wheel and thereby couple the drum with the roller so that, the drums being
connected by the said gearing and spindle they are compelled to partake of the
movements of the spring roller.
To adjust the width of the slit in the shutter, the lower drùm must be released
from engagement with the spring roller. For this purpose the spindle which is
furnished with a knob is adapted to be moved vertically or in the direction of its
length and carries a collar which then bears upon the toothed wheel of the lower
drum so that when the spindle is shifted the drum is moved out of engagement with
the pin of the spring roller. The drums can now be turned in either direction as
desired by means of the knob upon the spindle. If they be turned in the direction
to cause the cords to wind off the drums, the spring in the roller will draw a portion
of the blind back to a corresponding extent so that the slit will be widened. If on
the other hand the drums be turned in the direction to cause the cords to wind onto
the drums, the other portion of the blind will approach the first named portion the
slit being thus narrowed.
2
In order to indicate the width of the slit upon the exterior of the apparatus, a
toothed wheel is placed upon the spindle, and this wheel is brought, by the longi-
tudinal shifting of the spindle, into engagement with a toothed wheel upon which is
a fixed pointer which indicates the width of the slit.
Dated the 4th day of September 1894.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.

page_text: Improvements in or connected with Photographic Shutters.
We, WALTER OEHMKE, of 35 Dorotheenstrasse, Berlin, Mechanic, and CARL
PAUL GOERZ, of 140, Hauptstrasse, Schöneberg, near Berlin, Manufacturer, both
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:-
Our invention relates to a photographic instantaneous blind shutter, in which the
slit in the blind is capable of being narrowed or widened by means of a knob placed
outside the apparatus, according as it is desired to give a longer or a shorter
exposure.
In the accompanying drawing,-
Figure 1 is a section of a photographic camera having a blind shutter with our
improvements applied thereto; and,
Figure 2 is a view of part of the mechanism drawn to an enlarged scale.
The blind is made in two portions J, J' stretched upon rollers R, R' and, when
the shutter is being set, the blind is wound onto the roller R, and at the same time,
a spring situated in the roller R¹ is placed in tension. The exposure is effected
by releasing a catch-lever A when the blind is drawn by the spring on to the
roller R¹.
The two portions J, J¹ of the blind are connected together by cords S, S' which
are wound upon drums Z, Z¹ mounted loose upon the spindle of the roller R¹ and
having fixed thereto toothed wheels V and V' which engage with pinions K and K
situated on a spindle H. A spiral spring X presses against the drum Z and
constantly tends to force this drum towards the roller so as to cause a pin L upon
the roller to engage in a hole in the toothed wheel V and thereby couple the drum Z
with the roller so that, the drums Z, Z' being connected by the gearing V, VI,
K, K₁ and spindle H, they are compelled to partake of the movements of the
roller R¹.
To adjust the width of the slit in the shutter, the drum Z must be released from
engagement with the roller R. For this purpose the spindle H which is furnished
with a knob is adapted to be moved vertically or in the direction of its length and
carries a collar O which then bears upon the toothed wheel V of the drum Z so
that when the spindle H is shifted the drum Z is moved out of engagement with
the piu L of the roller R'. The drums Z and Z¹ can now be turned in either
direction as desired by means of the knob upon the spindle H. If they be turned
in the direction to cause the cords S and S' to wind off the drums, the spring
situated in the roller R' will draw the portion J₁ of the blind back to a corre-
sponding extent so that the slit will be widened. If ou the other band the drums
be turned in the direction to cause the cords to wind onto the drums, the portion J¹
of the blind will approach the portion J, the slit being thus narrowed.
In order to indicate the width of the slit upon the exterior of the apparatus, a
toothed wheel M is placed upon the spindle H, and this wheel is brought, by the
longitudinal shifting of the spindle, into engagement with a toothed wheel N upon
which is a fixed pointer which indicates the width of the slit.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. A photographic shutter consisting of a divided blind stretched upon rollers,
the two parts of which blind are connected together by cords wound upon drums
coupled to one of the said rollers so that when they are freed from it, by operating
a spindle furnished with a knob outside the apparatus, the drums can be turned in

page_text: either direction, the slit being thereby correspondingly widened or narrowed,
substantially as hereinbefore described.
2. In a photographic shutter of the kind claimed in the first claiming clause, an
indicator wheel which, when the drums have been freed from the spring-roller and
are operated to alter the width of the slit, will rotate and indicate the said width,
substantially as hereiubefore described.
3. The improved photographic blind shutter hereinbefore described and
illustrated in the accompanying drawing.
Date this 8th day of September 1894.
i this 8th day of September 1894.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.