Improvements in Photographic Shutters.
Year: 1888

page_text: Date of Application, 26th Nov., 1888
Complete Specification Left, 26th Aug., 1889-Accepted, 26th Nov.,
1889
PROVISIONAL SPECIFICATION.
Improvements in Photographic Shutters.
We EDMOND PERKEN FREDERIC LOUIS PERKEN and ARTHUR RAYMENT trading
as Perken Son & Rayment of .99 Hatton Garden London in the County of Middlesex
Wholesale Opticians and WALTER PEAD of 99 High Street Ramsgate in the County
of Kent Artisan do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in photographic shutters and consists of the
following arrangement of parts.
The shutter slide is made very thin of any suitable materials (advantageously thin
sheet metal) which travels loosely in guides advantageously formed in and by the
frame of the shutter.
On the upper end of this slide is a projecting pin or stud under which a spring
actuated lever secured to the said frame is placed and the end of the said lever is
held by a catch which may be actuated by a pneumatic releasing apparatus as is
well understood or otherwise as desired-the said lever on being released by said
catch throws up the shutter slide (and so gives the exposure) the slide falling again
by its own weight.
A lever actuated by the pneumatic release makes contact with the slide when open
and regulates the length of exposure or by any other convenient arrangement.
Dated this 26th day of November 1888.
TONGUE & BIRKBECK,
34, Southampton Buildings, London, W.C., Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Photographic Shutters.
We EDMOND PERKEN, FREDERIC LOUIS PERKEN, and ARTHUR RAYMENT trading
as Perken Son and Rayment of 99 Hatton Garden in the City of London Wholesale
Opticians and WALTER PEAD of 99 High Street Ramsgate in the County of Kent
Artisan 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 improvements in photographic shutters and consists of
the following arrangement of parts.
The shutter slide is made very thin of any suitable materials (advantageously thin
sheet metal) which travels loosely in guides advantageously formed in and by the
frame of the shutter.
On the upper end of this slide is a projecting pin or stud under which a spring
actuated lever secured to the said frame is placed and the end of the said lever
is held by a catch which may be actuated by a pneumatic releasing apparatus as
is well understood or otherwise as desired--the said lever on being released by
said catch throws up the shutter slide (and so gives the exposure) the slide
falling again by its own weight, or-for a very short exposure-assisted by
a spring.
A lever actuated by the pneumatic release makes contact with the slide when open
and regulates the length of exposure or by any other convenient arrangement.
A break arrangement may also be provided so as to hold the shutter open for the
purpose of focusing.
And in order that this invention may be easily understood and readily carried
with reference to the
into practice we will proceed to fully describe same
accompanying sheet of drawings.

page_text: Figure 1 is a view in elevation of the "front" of the apparatus with the several
parts in their normal positions.
Figure 2 is a similar view of the reverse side or "back" of the apparatus.
Figure 3 is a front view in elevation showing the parts set ready to give the longest
exposure.
"
on
"
and the positions of
Figure 4 similar view as Figure 3 showing the break",
parts for holding and retaining the shutter "open for focusing purposes.
Figure 5 is similar view as Figure 3 showing the position of parts set ready to
give the shortest exposure.
Figure 6 is a vertical section on line A B Figure 3.
Figure 7 is a separate view in front elevation of the shutter slide and Figure 8 is a
vertical edge view of same.
a is the shutter slide having stud a¹ thereon and sliding in the shutter frame formed
by plate b in front and plate e at the back.
is the " loading lever or catch for setting the shutter ready to let off
mounted on the front plate b by a bracket d' and pin d² with a coiled spring d³
to force said catch d up to the position shown in Figure 1.
e is the releasing trigger pivotted to the shutter frame at e¹ end at its end e²
engaging with the catch d as shown in Figure 3 while the movement of its other end e³
is limited by the removable stop pivotted to the shutter frame at f¹.
The "trigger" e is actuated by means of pneumatic pressure upon a piston in the
cylinder (as is well understood) two pins g g being secured to the said piston
and travelling in a slot provided for that purpose in the side of the cylinder.g
as shown.
. is a slide bar actuated by the spring which spring j and an eye on the lower
end k of the said slide bar both travel on the fixed rod m which slide har i is raised
up to the top and compresses the spring as shown in Figure 6 and is there held and
retained by the spring catch n (Figure 2) pivotted at n¹ on the back c of the shutter
frame part of the catch n extending beyond the framework and is there turned over
so as to form an anvil or knob z for the hammer y to strike when adjusted so to do.
A knob or projecting pin on the front of the slide bar i overlaps the top of the
slide a and travels in the slot provided in the back plate c for that purpose.
o is a pin on the trigger part e³ to engage in a notch or recess p formed in the
slide a when the break is applied by putting over the levers from the position
shown in Figure 3 to the position shown in Figure 4 and this puts friction on the
piston.
A knob x is mounted upon said catch d and a hammer or projecting pin y is also
mounted thereon capable of turning on its axis as and for the purposes hereinafter
explained.
The operation is as follows:-
In the first place the slide bar i must in every case first be lifted up until held by
the catch n.
Then to set the shutter "open " for focusing the catch d is pulled over until it
engages the trigger e and the breaks is put on (that is it is put in the position shown
in Figure 4) and the pneumatic pressure is then given in the usual way so releasing
the spring lever d which by means of the knob a¹ on the slide a throws up the
latter and the pin o engages in the notch p and retains the shutter open until the
breaks is taken off.
To give a lengthened exposure the stop lever f is moved into the position shown
in Figure 4 and the catch d loaded (as shown in Figure 3) as before described―
the breaks only being used for the purpose of focusing and is not used otherwise.
Pneumatic pressure is then put on the piston and kept on and so long as the operator
keeps this pressure up the pin o will engage in the notch p and keep open the
shutter until the pressure ceases when the piston will drop back and so move the

page_text: trigger e back and thus withdraw the pin o from the notch p and allow the slide a
to fall of its own weight or gravity.
An intermediate motion is obtained by putting the stop leverf back to the position
shown in Figure 3 thus limiting the movement of the trigger e and so preventing
the pin o thereon engaging with the notch p-thus when the shutter slide a is thrown
up by the spring lever d it immediately falls down again by its own gravity.
The shortest exposure of all is obtained by turning the hammer y into the position
shown in Figure 5 and when the catch d is released the latter will throw up the
slide a and then the hammer y thereon will strike z and release the slide bar i and
spring and these instantaneously descen ling the stud carries the slide a therewith
and thus the exposure given is instantaneous.
Thus it will be seen that the spring ; and slide bar are only used for one
particular exposure viz. the shortest; and the breaks is also only used for one
purpose viz. for focusing.
Thus a photographic shutter is produced of a very light and compact character and
very thin in cross section and can be attached to an ordinary photographic lens by
the set screws t t or can be adapted and used in any other desired manner.
Having now particularly described and ascertained the nature of this said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. A shutter slide such as a sliding freely in the shutter frame and unattached
to any other parts of the apparatus in combination and acting in conjunction with a
spring lever such as d which throws up the said shutter slide a and leaves the latter
free to fall again by its own gravity substantially in the manner and for the purposes
hereinbefore described and illustrated in the drawings annexed.
2. The combination of the shutter slide a and spring lever d with the releasing
catch or trigger e one part e³ of which engages with said lever d and the other part e³
having a pin o thereon to engage with a notch p on the slide a arranged and acting
substantially in the manner and for the purposes hereinbefore described and illustrated
in the drawings annexed.
Dated this 50th of A1000
TONGUE & BIRKBECK,
34, Southampton Buildings, Chancery Lane, London, W...
Agents for the Patentees.