SPRING- FOLDING CAMERA SHUTTERS, FOR THE MORE SPEEDY AND CONVENIENT MODE OF TAKING PHOTOGRAPHIC PICTURES THAN HAS BEEN HITHERTO ADOPTED
Year: 1856

page_text: LETTERS PATENT to Thomas Skaife, at present residing at Vanbrugh
House, Greenwich, in the County of Kent, for the Invention of "SPRING-
FOLDING CAMERA SHUTTERS, FOR THE MORE SPEEDY AND CONVENIENT MODE OF
TAKING PHOTOGRAPHIC PICTURES THAN HAS BEEN HITHERTO ADOPTED."
Sealed the 26th August 1856, and dated the 10th June 1856.
PROVISIONAL SPECIFICATION left by tho said Thomas Skaife at the
Office of the Commissioners of Patents, with his Petition, on the 10th
June 1856.
I, THOMAS SKAIFE, at present residing at Vanbrugh House, Greenwich, in
the County of Kent, do hereby declare the nature of the said Invention for
"SPRING-FOLDING CAMERA SHUTTERS, FOR THE MORE SPEEDY AND CONVENIENT MODE
OF TAKING PHOTOGRAPHIC PICTURES THAN HAS BEEN HITHERTO ADOPTED," to be as
follows:-
The Invention consists in substituting for the camera's ordinary dark slide
or shutter a pair of folding shutters, which are made to open and shut instan-
taneously inside the camera by means of a spring attached to or acting on the
axis of the shutters; and in consequence of the folding shutters being made to
open and shut inside the camera, the ordinary dark cloth, commonly made use
of by photographers to cover the aperture of the dark slide when taking a
photographic picture, is not required, as every injurious ray of light is effectually
excluded during the photographing a portrait or picture by means of the spring-
folding shutters.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Skaife in the Great Seal Patent Office on the
9th December 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
SKAIFE, as present residing at Vanbrugh House, Greenwich, in the County of
Kent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of June, in the year of our Lord One thousand
eight hundred and fifty-six, in the twentieth year of Her reign, did, for Herself,
Her heirs and successors, give and grant unto me, the said Thomas Skaife,
Her special licence that I, the said Thomas Skaife, my executors, adminis-
trators, and assigns, or such others as I, the said Thomas Skaife, my executors,
administrators, and assigns, should at any time agree with, and no others, from
time to time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "SPRING-FOLDING CAMERA SHUTTERS, FOR THE MORE SPEEDY AND
CONVENIENT MODE OF TAKING PHOTOGRAPHIC PICTURES THAN HAS BEEN HITHERTO
ADOPTED," upon the condition (amongst others) that I, the said Thomas Skaife,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Thomas Skaife, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
(that is to say)
My Invention consists, in the first part, in substituting for the ordinary dark
slide or shutter, made use of in the camera for covering the sensatized plate, a
pair of folding shutters, which being mounted, hung, suspended, or poised upon
axes, hinges, or pivots, are so arranged as to open and shut inside the camera,
by means of a small cord or band passing wholly or partially round, and con-
nected with two drums, or cylinders, or levers, or studs, fixed one on each
prolongation of the axes of the shutters, which project outside the camera, or
in some cases on the shutter axes themselves. On the surface of the said
drums (which arrangement I generally prefer), and so as either to connect

page_text: them or not, is fixed an india-rubber elastic band, or any other spring, in such.
a way, that when the drum or drums from any force are caused to rotate, tlie
action of the springs, when the force is removed, will bring them back to their
original position. When a picture is required.to be.photographed, the shutters,.
which are fixed in a frame at or near the back of the camera, or to the camera
back, and cover the sensatized plate, are opned by the operator gently pulling
or pressing with the tip of his finger the centre part of that fold of the cord,
so as to cause the drums: to rotate; when these have each revolved a quarter
of a circle the shutters are fully opned, their faces being at. right angles to
their first position and to the sensatized plate. The shutters are kept in this
position during the. requisite time by retaining the cord with the tip of the
finger, or by placing it behind a projecting stud provided for it on the shutter
frame; when the shutters require to be closed, the cord is detached from the
finger or from the retaining stop by the finger, or otherwise, and they instantly.
close by the action of the before-mentioned india-rubber band or other springs
upon the drums on the shutter axes. When the shutters are large, to prevent
them swinging open in their passage, to and from, when out of the camera, I
apply two additional closing springs, of steel, india-rubber, or other clastic
material; one spring acts on the shutters at the bottom near the. junction, the
other at the top, both springs being so fixed on the frame, containing the
shutters, that when it is dropped or pressed into its place in the camera, the
weight of the frame and its containing shutters at once detach the two springs,
leaving the shutters free to be opened by the action before described.
The second part of my Invention consists in adapting a second pair of
shutters, similar to the former, to be opned and closed by a like arrangement
an movement, and fixed or attached to that part of the camera a little in front
of the inner face of the lens, so that when shut or closed they will exclude the
light by covering the lens. The object of this second pair of shutters is to
keep the lens covered until the first pair is at least three quarters opened;
when the second pair is fully opened during the conclusion of the movement,
which opens the first; thus, supposing the. first pair of shutters, which covers
the plate to be photographed, so arranged as to open and close in a second of
time, then the second pair which covers the. lens is opned and closed in one-
fourth of a second; this is effected by extending the cord which opens the
second pair of shutters to within an inch or so of the frame which contains
the first pair, and there attaching it by the middle to a hook, which slides in a
groove fixed in the upper surface or top of the camera, and opposite to a
similar hook and groove fixed in the frame containing the first pair of shutters;
this second hook is attached to the finger ring of the first pair of shutters, placed

page_text: in the centre of the opening cord, by means of a piece of gut or strong thread.
When a picture is required to be photographed by the double action of the two
pairs of shutters, the exposure frame, containing the first pair or plate shutters,
is placed in its position in the camera, and the hook attached to the finger
ring drops over the hook attached to the centre of the opening cord of the
second pair or lens shutters, so that when the ring in the opening cord of the
first pair is pulled towards the operator by the finger, both pairs of shutters
are opened thereby, and when the ring is let go, both pairs immediately close
by the action of the elastic band or springs upon the drums, as before mentioned.
Should it be preferred, in some cases cach pair may act separately, after the
manner and by the means first mentioned. In order still further to accelerate
the speed by which the light may be admitted and shut off from the sensatized
plate in the camera, when an almost instantaneous action is required in obtain-
ing a picture of an object or of some rapidly moving body, I take a thin metal
plate of steel or other hard substance, in length at least three diameters of the
lens, and in breadth about one diameter, having a circular aperture in its
centre nearly equal to one diameter of the lens; this plate I place between
two glass grooves or guides, one of which is fixed upon each edge of the lens
and parallel to the other, and by means of a small cord or silken thread
attached to one end of the plate, I draw it along the glass guides until it is
within about an inch and a half of the side of the camera towards which it
is drawn, there it comes in contact with a spring, which yields to the plate as
it advances, and until it fully covers the lens. To retain the plate in that
position until the lens requires to be uncovered, I use a small bolt, made of
steel, or some other hard polished substance, and so placed that one end gently
presses against the steel plate when it covers the lens, and by means of a stop
retains it in that position; the other end of the bolt being outside the camera
serves the purpose of a trigger, so that when the operator has sighted the
moving object he wishes to take a picture of (having for that purpose the
camera mounted upon a swivel stand, moving it until the aperture of the lens
has covered the object), he then touches or presses the trigger with the tip of
the finger and thumb, or by other connexion, and the stop on the plate is
released by the motion given by the trigger, and darts along the grooves or
guides with great rapidity, at the same time fully exposing in the middle of its
course the object to be photographed to the sensatized plate; the shutters
covering the picture are then closed, either by a connexion with the trigger, or
in the manner before described, and the development and fixing of the picture
proceeded with.
It has been already mentioned that the one end of the small cord or silken

page_text: thread by which the plate is drawn along the grooves against the spring is
attached to the plate; the other end of the thread is passed through a smal
india-rubber tube, in length about one diameter of the lens, and is then fixed
to the end of the tube, care being taken before fixing the thread that a part of
it (the thread) in length equal to two diameters of the lens should appear
between the inner end of the tube and the plate to which the other end is
attached; this done, the plate is placed between the two glass grooves, and the
other end of the india-rubber tube, with its contained thread, being pressed
through a small aperture in the camera side, until the aperture is closed by a
projecting shoulder on the inner end of the tube. When this shutter plate is
required to be used, the end of the india-rubber tube, which projects outside
the camera, is taken between the finger and thumb, and pulled outwards to the
extent of about two diameters of the lens, when a slight click of the trigger,
passing over a stop on the plate, gives notice that the plate has been pulled
into its proper position for being projected; the india-rubber tube is then gently
allowed to contract itself into its original dimensions, when the thread, by the
action of the contractile force of the india-rubber tube, becomes coiled within
it, after the manner of the tail of a snake when prepared to spring, so that
when the plate is projected, by the trigger being pressed, the thread is forced
from the tube, and darting forward, occasions no perceptible obstacle to the
rapid motion of the plate along the glass guides. The plate may be projected
at any angle to the horizon, and when made to descend perpendicularly an
increase of speed is given thereby, in proportion to the diminished friction on
the guides and the gravity of the plate. The speed may be still further
increased by placing a magnet at the terminous of the glass guides, so as to
act upon and attract the steel plate shutter towards it.
In order to illustrate more clearly the foregoing description of my Invention
the following Drawings are appended, so as to exhibit the mode in which the
different motions and actions are effected, the letters indicating the several
parts in one Figure corresponding with those of the other. The sizes, dimen-
sions, and arrrangement of each may be varied, but the general principles of
construction described in the Specification must be retained.
EXPLANATION OF DRAWINGS.
Figure 1 in the Drawings is a plan of a camera. A, the lens; B, the
exposure frame; a, a, the little drums upon the shutter axes, which are shewn
prolonged to the outside of the exposure frame, having the studs b, b, to which
is fixed the clastic band c and the cord or thread d, d, which latter has the
finger ring fixed in its centre; this arrangement shews the shutters f. f.

page_text: closed upon the sensatized plate. When the finger ring is pressed or pulled
into the position shewn by the dotted lines, the drums are made to rotate, the
elastic band becomes distended, and the shutters are thrown open.
Figure 2 shews the arrangement when a similar pair of shutters covers the
lens, the letters indicating the like parts as in Figure 1, the interior of the
lens and the sensatized face of the plate being covered by the shutters.
Figure 3 shews the arrangement when the shutters are thrown open.
Figures 5 and 6 are sections of the camera upon the lines C, D, of Figures
2 and 3, shewing the position and arrangement of the lens shutters when closed
and open, as f, ƒ³, and ƒ³, ƒ'.
Figure 4 is a section of the camera upon the line C, D, in Figure 1, shewing
the arrangement of the plate in the front of the lens. 0, 0, the glass guides
or grooves; p, the shutter plate, having the circular aperture in the centre;
m, the trigger; n, the projecting spring; r, the silk cord or thread; s, the
india-rubber tube containing the thread r; A, the lens covered by the plate p.
In this view the shutter plate has been drawn close up to the camera; the
india-rubber tube is shewn distended containing the thread.
Figure 4 shews the plate ready to be projected, the india-rubber tube being
now allowed to contract to its usual dimensions containing the thread coiled
within it.
Figure 4 shews the plate after it has been projected. The general arrange-
ment of the trigger and the projecting spring may be varied.
Figure 7 is an isometrical view of the camera, shewing in detail the before-
described arrangements.
In witness whereof, I, the said Thomas Skaife, have hereunto set my
hand and seal, this Ninth day of December, in the year of our Lord
One thousand eight hundred and fifty-six.
JAMES WRIGHT,
10, Alfred Place,
Newington Causeway.
THOS SKAIFE. (L.8.)
Witness.