Year: 1896

page_text: GEORGE HOUGHTON 89 High Holborn Photographic Dealer and Manu-
facturer, and WILLIAM ALBERT EDWARDS, Weston House, Broadway, Tooting,
Camera Fitter, do hereby declare the nature of this invention to be as follows:
The object of our invention is to provide an apparatus known as a photographic
shutter, more especially for use in studio cameras, which shall give a maximum
aperture when opened in comparison to its external dimensions. In most of the
present forms of shutters, the size of aperture compared with the external dimen-
sions renders them impracticable for internal use with many forms of cameras.
The method we adopt is as follows.
We take two frames of wood or other suitable material, the openings being
sufficient to avoid any obstruction of the rays of light passing through the lens
towards the sensitive plate. The external dimensions of said frames are sufficient
to allow for the thickness of strip inserted between them towards the outside and
to form a space in which the segments of shutter lie as hereinafter described.
The said frames and strips when fixed together forming practically a hollow frame.
At each corner of space in hollow frame we pivot a suitable arm which extends
to the opposite nearest corner and is free to turn on its pivot, each arm turning in
a uniform direction. Attached to the aforesaid pivoted arms are flexible folding
blinds, somewhat of a quadrant shape when open, and which forms an opaque
screen over shutter aperture when the pivoted arms lie across the centre of said
aperture. Each arm being operated by a spring and meeting the one pivoted on
the further corner. Each pair of arms being furnished with a light-tight joint.
In the process of opening shutter the pivoted arms are turned outwards the blinds
fold up and lie together with said arms in the space in hollow frame. This
operation is effected by means of a crank or pneumatic ball and tube from the
outside of camera. The arms are connected together by means of a flexible tape
running over pulleys which are fixed to said arms at their pivoted ends or by a
system of links working on the bell crank principle so that they all move together
when motion is imparted to either one. The normal position of pivoted arms is
to lie, across shutter aperture. Another modification of our invention is to attach
a system of strips of vulcanite celluloid or other suitable material to each, arm in
place of the flexible folding blinds. These strips open and close on the principle
of a fan and are operated by the same means as the flexible blinds.
In another method a system of plain flexible blinds are attached to pivoted arms
and are drawn outwards from the hollow frame (slots being provided for that
purpose) (when the shutter aperture is opened) by means of spring arms attached
to the free edge of blind on the outside of aforesaid hollow frame. The said spring
arms pulling the blinds free from the interior surfaces of camera, and in such
manner as to offer no obstruction to the photographic image.
A still further modification applicable where the interior dimensions of camera
permits is to use rigid blinds or shutters which simply project outside of hollow

page_text: frame when shutter aperture is opened. This plan will be especially suitable for
many forms of hand cameras and for use on the outside of studio or field cameras
of any kind.
Dated this 19th day of September 1896.
GEORGE HOUGHTON,
WILLIAM ALBERT EDWARDS.
GEORGE HOUGHTON 89 High Holborn London W.C. WILLIAM ALBERT EDWARDS
Weston House Broadway Tooting S.W. do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The object of our invention is to provide an apparatus known as a photographic
shutter, more especially for the use in studio cameras and which shall give a
maximum aperture when open in comparison to its external dimensions.
In most of the present forms of shutters the size of aperture compared with the
external dimensions renders them impracticable for internal use in many forms of
cameras.
Reference to the accompanying drawings will assist to make the following
description clear.
We take two flat frames of wood or other suitable material, shown at a aa a
Fig. 1. and partly at a Fig. 2. (In which the top flat frame is removed for the purpose
of showing the internal arrangements).
The openings in said frames being large enough to avoid any obstruction of the
rays of light passing through the lens towards the sensitive plate, and the external
dimensions sufficient to allow for the thickness of a narrow frame partly shown at
cc Fig. 2, to be inserted between them. The whole when screwed together forming
practically a hollow frame, the internal space of which receives the segments of
shutter as hereinafter described.
At each corner of said hollow frame we pivot a suitable arm, two of which are
shown at Figs. 1 & 2. Each arm being free to turn on its pivots and of
sufficient length to reach nearly to the axle of the opposite near arm, as shown at e
Fig. 2 when the shutter aperture is open, and which lie diagonally across aperture
when closed, meeting the arm pivoted on the opposite diagonal corner as shown
in Fig. 1. Each pair of arms being suitably recessed at f Figs. 1 & 2 to form a
stop, and a light tight joint by overlapping each other.
To the said pivoted arms are attached flexible folding leather or cloth
sections ggg Figs. 1 & 2 whose opposite sides are attached to the inner
surface of narrow frame c c Fig. 2. These with the pivoted arms are arranged
up and down to clear each other in opening and closing, and form an opaque screen
when pivoted arms lie across shutter aperture as shown in Fig. 1.
To all the arms are fixed short cranks at their pivoted ends hhhh Fig. 1. The
pivot on one side being extended for that purpose, the said cranks being connected
together by means of pivoted rods iii Fig. 1, thereby ensuring simultaneous
motion being communicated to all the others when one arm is operated, and
causing a uniform opening and closing of aforesaid aperature.
Reference to drawing Fig. 1 will clearly show the general arrangement of arms,
cranks, rods, and segmental blinds.
To one of the arms, and near its pivoted end we attach a spring J Fig. 1. which

page_text: is fixed at its other end to the interior of hollow frame. The said spring being so
fixed and regulated as to keep the aperture closed as shown in Fig. 1.
To open the shutter we attach a pneumatic cylinder to one of the cranks as
shown at K Fig. 1. The cylinder being operated by a pneumatic ball and
tube Fig. 1. A section of said cylinder and fitting, which is of special con-
struction is shown at Fig. 3 (to which the following reference letters refer) and is
made as follows.
To a nozzle piece M. we attach an india rubber finger stall N. and screw over same
an inner tube 0. 0. we then double the finger stall within itself as shown at p. An
air passage Q being provided in the nozzle communicating with the interior of
finger stall. We then provide another outer tube or cylinder R R. which slides
freely over the aforesaid inner tube and in which is screwed a wooden pin S.
projecting downward into the finger stall p. To the nozzle U we connect a
pneumatic ball 7 Fig. 1 which on being pressed supplies air to the interior of
finger stall thereby exerting a lifting power on the outer sliding tube or cylinder,
through the medium of the wooden pin. The said outer tube or cylinder being
connected to the cranks of the shutter arms by means of the rod t Figs. 1 and 3
imparts the power sufficient to overcome the tension of spring thereby opening
shutter aperture. When the pressure on ball is released the spring operates and
closes said shutter aperture.
It is obvious that there are various modifications possible in the minor details
of constructing our invention. For example we might substitute strips of
vulcanite celluloid or other suitable material to take the place of folding blinds.
The said strips being so arranged as to open and close in the manner of a fan,
when the arms are rotated.
It is also possible to apply various methods of operating the said arms such as
by means of a cord or chain running over pulleys attached to the aforesaid extended
pivots. These modifications will not interfere with the essential principle of our
invention which consists of the opening of a shutter aperture from the centre by
means of radiating arms which move simultaneously and to which segmental
folding blinds, or screens, are attached as hereinbefore described.
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 shutter consisting of a hollow frame furnished with radiating
arms to which are attached flexible or folding blinds or screens substantially as
described.
2. A photographic shutter consisting of a hollow frame combined with a method
of opening and closing aperture of same substantially as described.
3. A photographic shutter consisting of a hollow frame furnished with radiating
arms which are rotated simultaneously substantially as described.
4. A pneumatic cylinder operated by means of a turned in finger stall in con-
nection with a pneumatic ball and tube substantially as described.
Dated this 21 day of June 1897.
GEORGE HOUGHTON,
WILLIAM ALBERT EDWARDS.