Improved Means of Enveloping Sensitive Photographic Films and Plates for Transport and Exposure in the Camera.
Year: 1898

page_text: Improved Means of Enveloping Sensitive Photographic Films and
Plates for Transport and Exposure in the Camera.
I, GEORGE CORPE WHITFIELD, of Monk Sherborne, Eastbourne, in the County
of Sussex, Gentleman, do hereby declare the nature of this invention to be as
follows:-
My invention relates to the means of enveloping photographic films (or plates)
before and after use, and of holding and exposing the said films or plates in the
camera, and the invention consists of improved envelopes or wrappers wherein
the films or plates are enclosed when packed for sale and which are adapted to
serve also as dark backs or holders by means whereof the films or plates may
be introduced into, exposed in, and removed from, the camera.
I make a combined wrapper and dark back of paper, cardboard, or other suitable
material of such cheap construction and in such a manner that one may be provided
for each film, or each pair of films, the shutter of the dark back forming a sheath
enclosing the film or films. With this object the shutter of the dark back is made
like a bag-envelope of non-actinic paper or card closed at the outer end which
may project from the body or be provided with a tab to enable the shutter to be
drawn, the inner end of the shutter being open. The body of the dark back in
which this shutter is received is also like a bag-envelope open at the outer end
and having an exposure aperture in one or both sides. The film (or a support
on which it may be mounted) may be attached to the closed end of the body
portion by wire staples or eyelets or by an adhesive material or otherwise, so that
when the sheath-like shutter is drawn out the film will be retained at the exposure
aperture. The stop which limits the drawing out of the shutter may be a projection
glued on, or may be formed by stamping up the paper itself, this stop also
serving to bend up the margin of the exposure aperture slightly at the inner
end so as to avoid all liability of the end of the shutter catching when pushed
in after exposure. Each such dark back may be adapted to hold two films (or
plates) back to back (with intervening non-actinic material) within the same
bag-like shutter and to expose them in succession, the body portion being in that
case provided with an exposure aperture at both sides. This combined wrapper
and dark back may be supported by a removable back board hinged or otherwise
attached to the camera, the body portion of the dark back being gripped
prevented by studs or other fastenings from drawing out along with the sliding
shutter, a light-tight closure being made by velvet or otherwise if necessary at
the end where the shutter draws out. Instead, however, of the shutter being
drawn out beyond the body of the camera it may, being flexible, be retained
wholly within the camera body when drawn, the shutter being in that case.
operated by the following means:-Within the camera is mounted a rubber-
covered roller or pair of rollers between which and another roller or pair of rollers
mounted on the back board the shutter is nipped and so directed into the camera
or

page_text: body as to cause it to be drawn or closed by turning the one roller or pair of
rollers from the outside, the shutter when so drawn being wholly within the camera
body.
In order to remove the film for development, it is only necessary to cut off the
closed end of the holder and of the film which is fastened thereto.
Dated this 3rd day of August 1898.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.
Improved Means of Enveloping Sensitive Photographic Films and
Plates for Transport and Exposure in the Camera.
I, GEORGE CORPE WHITFIELD, of Monk Sherborne, Eastbourne, in the County
of Sussex, Gentleman, 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:
My invention relates to means of wrapping or enveloping cut photographic films
or plates and of holding and exposing them in the camera and the invention
comprises envelopes or wrappers wherein the films or plates may be enclosed when
put up for sale by the maker the said envelopes or wrappers being adapted to
serve the purpose of dark backs by means whereof the films or plates may be
placed in position in the camera, may be exposed, and be removed after exposure,
without being withdrawn from their original wrappers.
The invention also comprises the means by which the operation of the dark slide
within the camera is effected.
The invention will be described with reference to the accompanying drawings
forming part of this specification wherein Figure 1 represents a longitudinal
section of the rear portion of a camera body, shewing the combined wrapper and
dark slide in position and the means of operating the same for the purpose of
effecting the exposure of a film or plate, the shutter being supposed to be partially
raised. Figure 2 is a similar view shewing the back of the camera thrown open
for the purpose of placing the combined wrapper and dark slide in position
therein. Figure 3 is a horizontal section taken at the plane of the rollers by
which the shutter of the dark slide is operated. Figure 4 is a similar section
taken below the rollers and shewing the dark slide in position. Figure 5 is an
inside face view of the back of the camera and of the combined wrapper and dark
slide carried thereby. Figure 6 is a face view of the combined wrapper and dark
slide, the shutter being partially raised. Figure 7 is a vertical section of a
combined wrapper and dark slide for a single film or plate, and Figure 8 is a
similar view of a double wrapper and dark slide, the thickness of the material
of which the parts are made being greatly exaggerated. Figures 9 and 10 are
horizontal sections corresponding respectively to Figures 7 and 8, and Figure 11
is a horizontal section of the shutter of the dark slide, the thickness of the
material being greatly exaggerated in these figures also. The same letters of
reference denote the same parts in all the figures.
For the purposes of my invention I make a combined wrapper or envelope and
dark slide for each film or each pair of films (as the case may be) the shutter of
the dark slide being made in the form of a sheath enclosing the film or films.
The frame a of the envelope and dark slide may be made of stout paper, stiff

page_text: calico, or cardboard which may be of the form shewn in Figure 6 the film A being
placed within it and secured by suitable means such as wire staples c driven through
the frame and film so that the latter is securely fixed in position in the frame.
Instead of wire staples, metallic eyelets may be riveted in holes punched through
the whole as will be readily understood.
The shutter of the dark back is of flexible material such as non-actinic paper
or calico, and is made in the form of a bag-like sheath open at its inner end
so as to be adapted to receive the film within it, as shewn in Figures 7, 9, and 11,
when the sheath is slid within the frame; the outer end of the shutter being closed,
and the closed end d projecting beyond the end of the frame of the dark slide
so as to enable it to be gripped and withdrawn by the means hereafter described.
In the case of a dark slide for two films there would be (as shewn in Figures 8
and 10), an exposure aperture at back as well as at the front of the frame and
the two films would be secured therein back to back with an intervening piece of
non-actinic paper f, and be received within the sheath-like shutter as before.
In either case the inner open end of the sheath-like shutter when in its closed
position is so far received within the end 6 of the frame that light is excluded from
the contained film or films. Instead of a single frame serving for two films, two
complete single-film frames might be used, each containing a film and having
its own shutter, the frames being secured back to back and the shutters being
joined together at top so as to be raised and lowered as one.
For the purpose of exposure in the camera the combined wrapper and dark
slide is supported by a back-board g which may be hinged to the rear of the
camera body and makes a light-tight closure thereof, the dark slide being received
between side flanges y¹ and its lower end being received in a wire clip h acting
as a stop.
m
The drawing of the shutter is effected by mechanism within the camera and in
such manner that the shutter when drawn, remains wholly enclosed within the
camera body. For this purpose there is mounted in a recess across the inner face
of the backboard g a rubber covered roller i whose journals may be supported
to turn in bearings in spring arms and in the body of the camera is' mounted
another similar roller kin such position that when the dark slide is placed in position
in the backboard g and the latter is closed and locked by any suitable fastening,
the rollers will be pressed together with the tab-like end of the shutter nipped
between them with a pressure due to the elasticity of the springs ; sufficient to
cause the shutter to be drawn by the revolution of the rollers. Or the roller i
may be mounted in fixed bearings and the roller k may be mounted in spring
bearings, or both may be mounted in fixed bearings if the thickness of the elastio
covering of the rollers is such as to allow of yielding sufficiently. In order to
further guard against slip, the rollers might be geared together by pinions
on their axles, but the adhesion of the roller k may alone be sufficient, the roller i
turning idly. The rollers are formed of metal axles covered preferably with tubing
of soft rubber (or it might be other soft and elastic material) which may be plain
or corrugated to increase the bite, and motion is imparted to the roller k by a
spur wheel n in gear with its pinion m the spindle of said spar wheel passing
through the side of the camera body and being provided with a folding handle o
for turning it, the ratio of the gearing being preferably such that a single
revolution of the spur wheel n is sufficient to withdraw the shutter to the proper
extent. For this purpose the turning of the handle in either direction is limited
by an arm on the spindle coming in contact with a stop pin q so that (the moving
of the shutter in or out the exact distance required being thereby determined)
no stop on the shutter itself is required. The shutter on being drawn out by
the action of the rollers must not be wholly withdrawn from the film, the end
of which remaining entered within the shutter will not obstruct the return of the
shutter. The shutter becomes completely flattened or collapsed as it passes
between the rollers and being very flexible it is readily deflected on coming in

page_text: contact with a curved guide r at the upper part of the camera body whereby it
is caused to pass in a horizontal forward direction as shewn in Figure 1, into a
spaces provided for its reception so that when drawn it remains entirely within
the camera body. In order to prevent the inner end of the shutter when it is
pushed in, from catching against the edge of the bottom flap 6 of the slide, a
light tongue t of celluloid or other flexible material is mounted on the bottom
of the camera body so as to project by its downwardly curved extremity over the
edge of the flap band so guide the end of the shutter home. This tongue t also
assists in retaining the slide in position when the shutter is drawn out.
In the case of a cheap camera the roller mechanism may be omitted, in which
case the shutter would preferably be made of thin cardboard or other equally stiff
but flexible non-actinic material and the end of the shutter would project
through a velvet-lined slit left for its passage between the upper end of the back-
board g (which would in that case extend up to the top of the camera) and the
edge of the top against which the board closes. The front of the shutter would
in this case carry a projecting stop adapted to come against the camera top when
the shutter is raised the proper distance for effecting the exposure of the film;
the stop serving to prevent the shutter being wholly withdrawn from the film
which would otherwise prevent the shutter being lowered after the exposure.
In order to remove the film from the dark slide for the purpose of development
it is only necessary to cut off the closed end of the dark slide and the attached
portion of the film, at a point just above the staples c or equivalent fastening.
The invention may be used for plates of glass or other translucent material used
instead of celluloid as a support for the sensitive coating, provided that the plates
are sufficiently thin. The plates would be fixed in position in the paper or other
frame by an adhesive material at the back of the plate.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:
1. A combined wrapper or envelope and dark slide for holding and exposing
a photographic film or plate formed of a body portion made of paper, card, calico,
or equivalent material and having the film fastened therein by its bottom end
substantially as described, in combination with a sliding shutter in the form of
a bag-like sheath open at the inner end within which the film or plate is received
and capable of being withdrawn so as to uncover the film or plate substantially
as described.
2. In a combined wrapper or envelope and dark slide for holding and exposing
a photographic film or plate, the employment of a shutter in the form of a bag-
like sheath of non-actinic paper or equivalent material open at the inner and
closed at the outer end, adapted to slide in a suitable body portion or slide and
to receive within it the film or plate secured in the said body portion or slide.
3. In a photographic camera the combination with a combined wrapper or
envelope and dark slide substantially as described, of a hinged or removable
backboard adapted to close the back of the camera and to support and hold the
dark slide and to permit the withdrawal of the shutter from the slide as described.
4. In a photographic camera the combination with a combined wrapper or
envelope and dark slide substantially as described, of a hinged or removable
backboard adapted to support the dark slide and of a pair of rollers and gearing
for revolving the same, the rollers being adapted to nip the shutter between them
and by their revolution to withdraw and return the shutter as described.
5. In a photographic camera the combination with a combined wrapper or
envelope and dark slide substantially as described, of a removable backboard
adapted to support the dark slide, a pair of rollers mounted the one on the
backboard and the other on the camera body so as to be adapted to nip the shutter

page_text: between them and by their revolution to move it in or out, gearing for revolving
the rollers, and a guide for deflecting the shutter when withdrawn, in a forward
direction within the upper part of the camera substantially as specified.
Dated this 3rd day of May 1899.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.