Improvements in Changing Boxes or Backs for Photographic Cameras.
Year: 1894

page_text: Date of Application, 8th Mar., 1894
Complete Specification Left, 8th Dec., 1834-Accepted, 12th Jan., 1895
PROVISIONAL SPECIFICATION.
Improvements in Changing Boxes or Backs for Photographic
Cameras.
We, ANDREW RIDDELL, Photographic Dealer of 134 St. Vincent Street and
JOHN SINCLAIR, Bootmaker, of 150 Buchanan Street both in the City of Glasgow
do hereby declare the nature of this invention to be as follows:-
This invention relates to changing boxes or backs for carrying the sensitive
plates or films for exposure in photographic cameras and it has for its objects
mainly to dispense with the use of sheaths for the plates or films whilst providing
protection against access of light to the spare plates during the exposure of any
single plate and generally to facilitate the operations of changing and recording
the changes of plates..
The improved apparatus comprises a light-tight box adapted to be fitted to the
back of a photographic camera into which box the plates or films are deposited so
as to rest vertically on edge on the bottom of the box when in use and either in
contact with each other or separated merely by strips of paper gummed at the
edges of the plates or films in order to protect their sensitive surfaces from actual
rubbing contact with the surfaces of the adjoining plates or films. The plates or
films are inserted from the back of the box, which is preferably hinged or otherwise
fitted to open up for access to the interior and a sliding plate or shutter is fitted
near the front of the box the plates or films being pressed into contact with each
other and towards the sliding shutter by a spring fitted at or on the back of the
box. The top or one end of the box is either open or has two slits formed in it,.
one in proximity to the back through which the plate to be exposed is withdrawn
and the other at the front through which the plate is inserted for exposure in front
of the sliding shutter, the open or slitted end of the box being encased or covered
by a flexible light-tight bag or hood so as to protect the plate whilst being removed.
from the rear to the front of the box for exposure.
One plate at a time is lifted from the back of the box either by hand or by
means of a sliding bar or rod fitted in the hinged back and having a catch or
projection at its lower end which engages the bottom edge of the plate and draws
up the latter through the rear slit into the flexible bag, the forward pressure on
the plates being relieved during this operation by pressure of the hand on a knob
or lever which acts to retract the spring bearing on the plates. The plate thus
lifted out is grasped through the flexible bag or hood and inserted through the
front slit into position in front of the sliding shutter where it may be exposed in
uncovering the lens of the camera. During such exposure the spare plates are
protected from light by the sliding shutter which then remains closed but after
exposure and re-covering the lens the sliding shutter is raised by means of: a
suitable knob or catch piece within the flexible bag whereupon the exposed plate
drops or is pushed back into contact with the spare plates behind the shutter
which is thereafter closed to protect the plates during the succeeding exposure.
During exposure, the plate placed in front of the shutter is or may be kept in
register by means of light springs fitted on the front of the shutter and on the
withdrawal of the shutter it may either be dropped by gravity into the box or as is
preferred it is pressed back by the projecting ends of light wire or other springs
which are normally pressed forward by the shutter to lie in front of the edges of
the plate being exposed..
'

page_text: In one side of the box is fitted an indicator disc or dial bearing on its face a
series of numbers one of which at a time is. visible through an orifice. This
indicator is operated so as to advance by one the number exposed through the
orifice by the action of withdrawing and replacing the sliding shutter the edge of
the shutter or a projection on it engaging one of a series of teeth or notches on
the indicator and turning it to the requisite extent at each exposure so as to
indicate the number of plates exposed.
Dated this 7th day of March 1894.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.
.
Improvements in Changing Boxes or Backs for Photographic
Cameras.
We, ANDREW RIDDELL, Photographic Dealer, of 134^ Saint Vincent Street,
and JOHN SINCLAIR, Bootmaker, of 150 Buchanan Street, both in the City of
Glasgow, 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 changing boxes or backs for carrying the sensitive
plates or films for exposure in photographic cameras and it has for its objects
mainly to dispense with the use of sheaths for the plates or films whilst providing
protection against access of light to the spare plates during the exposure of any
single plate and generally to facilitate the operations of changing and recording the
changes of plates.
The invention is illustrated in the accompanying drawings under one modification
in vertical section at Fig. 1. on the line x-x of Figure 2 in back view with the
back of the box removed at Figure 2, and in horizontal section at Fig. 3 on the
line yy, Figure 1, and under another modification in vertical section at Fig. 4 on
the line of Figure 5 and in horizontal section at Fig. 5 on the line ww of
Figure 4.
.
Referring to the modification illustrated by Figs. 1, 2 and 3 the improved
apparatus comprises a light-tight box A adapted to be fitted to the back of a
photographic camera into which box A the plates B or the films are deposited so
as to rest vertically on edge on the bottom of the box when in use and either in
contact with each other or separated merely by strips of paper gummed at the
edges of the plates or films in order to protect their sensitive surfaces from actual
rubbing contact with the surfaces of the adjoining plates or films. The plates or
films are inserted from the back C of the box, which is preferably hinged or
otherwise fitted to open up for access to the interior and a sliding plate or shutter D
is fitted in a grooved near the front of the box the plates or films being pressed into
contact with each other and towards the sliding shutter D by a spring E fitted at
or on the back of the box. The top or one end of the box is either open or as
shewn has two slits G, H, formed in it, one G which is in this case covered by a
spring flap I in proximity to the back through which the plate to be exposed is
withdrawn and the other H at the front through which the plate is inserted for
exposure in front of the sliding shutter D the open or slitted end of the box being
encased or covered by a flexible light-tight bag or hood J so as to protect the
plate B whilst being removed from the rear to the front of the box for exposure.
One plate at a time is lifted from the back of the box A either by hand or by
means of a sliding bar or rod K fitted in the hinged back C having a hand grip k
and a catch or projection at its lower end which engages the bottom edge of the
plate B and draws up the latter through the rear slit G into the flexible bag J the

page_text: forward pressure on the plates B being relieved during this operation by pressure
of the hand on a knob or lever L which acts to retract the spring E bearing on the
plates B. The plate thus lifted out is grasped through the flexible bag or hood .J
and inserted through the front slit H into position in front of the sliding shutter D
where it may be exposed on uncovering the lens of the camera. During such
exposure the spare plates B are protected from light by the sliding shutter D
which then remains closed but after exposure and re-covering the lens the sliding
shutter D is raised by means of a suitable knob or catch piece d' within the flexible
bag whereupon the exposed plate drops or is pushed back into contact with the
spare plates behind the shutter which is thereafter closed to protect the plates
during the succeeding exposure. During exposure, the plate B placed in front of
the shutter D is or may be kept in register by means of light springs M fitted on
the front of the shutter and on the withdrawal of the shutter it may either be
dropped by gravity into the box or as is preferred it is pressed back by the
projecting ends of light wire or other springs N which are normally pressed
forward by the shutter D to lie in front of the edges of the plate being exposed.
In one side of the box is fitted an indicator disc or dial O bearing on its face a
series of numbers one of which at a time is visible through an orifice P. This
indicator is operated so as to advance by one the number exposed through the
orifice by the action of withdrawing and replacing the sliding shutter D the edge
of the shutter or a projection on it acting on one end of a pawl Q the other end of
which engages one of a series of teeth or notches on the indicator O and turns it
to the requisite extent at each exposure so as to indicate the number of plates
exposed.
In the modification illustrated by Figures 4 and 5 the casing A is formed with
an opening in its end through which the plates are inserted and which is closed by
a light tight door A'. The upper end of the box A is cut away as shewn at a to
permit of the rearmost plate B being grasped by hand through the flexible bag Jį
and in the operation of the apparatus the rear plate is raised into the bag and
dropped in front of the opaque shutter-like plate D for exposure, in a manner
similar to that described with reference to Figures 1, 2 and 3. The plate being
exposed is kept in register at the front of the box by means of a spring blade or
wire R fitted in the rear wall of the box and carried on a rocking spindle or wire r
provided with a lever arm outside the box the spring serving to press forward
the whole of the plates. During the manipulation of the plates the pressure of the
spring is relieved or applied by acting either on the lever arm by hand, or as is
preferred by acting on a bell crank which is applied to operate the recording
device. This latter device is composed in this instance of a rotatory notched
ratchet disc T bearing around its face a series of consecutive numbers. The
notches t are formed preferably on the face of the disc T and each has impressed
on it one of the consecutive numbers and with these notches one arm t¹ of the bell
crank engages in succession as the bell crank is operated to act on the lever armr
serving to relieve and again apply the pressure of the spring R on the plates B.
As this relief and re-application of the spring pressure coincides with each exposure
of a plate the number of exposures is automatically recorded by the operation of
the bell crank S which at each action brings a fresh number on the disc in line
with a spring pointer U serving also to prevent movement of the disc during
retraction of the bell crank.
In both modifications the usual slide is or may be fitted in grooves in the box in
front of the sliding shutter D.
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. The improved changing box or back for photographic cameras the parts of
which are constructed, combined and arranged to operate substantially as described
with reference to the annexed drawings.

page_text: 2. In a changing box or back for photographic cameras the combination with
the box or case serving to hold the plates and a flexible bag or hood fitted thereon
of a sliding shutter adapted to protect the spare plates during exposure of a single
plate and to be withdrawn into the flexible hood or bag and inserted to cover the
exposed plate substantially as described.
Dated this 7th day of December 1894.
WALLACE FAIRWEATHER,
Chartered Patent Agent,
62, St. Vincent Street, Glasgow, Agent for the Applicants.