Improvements in Cameras.
Year: 1899

page_text: Improvements in Cameras.
I, JOHN EDWARD THORNTON, of Rokeby, Oldfield Road, Altrincham, Cheshire,
Manufacturer, do hereby declare the nature of this invention to be as follows:-
The improvements forming the subject of this invention relate to the design
and construction of photographic cameras whereby advantages of convenience to
the user and advantages in the manufacture are obtained.
Briefly a camera constructed according to this invention may comprise a base-
board to which a body is hinged at one end and a front at the other. The body and
front are connected by a bellows. The body may carry the plate or other sensitive
material. whilst the front carries the optical system comprising lens, shutter, and
accessories.
I prefer to construct the camera almost entirely of aluminium in the principal
parts not subjected to great wear, and to use brass for those parts such as struts
and the like which require greater strength. Other materials (including wood)
may be used where desirable, but using metal, as I do, permits of great lightness
combined with stiffness and rigidity, and also cheapness and accuracy in pro-
duction.
The body of the camera is made expansible, so that it may accomodate for
instance, when fully expanded three plate holders, or a roll holder, or a plate
magazine, which occupy about the same space, whilst when not expanded it may
only accomodate for instance one slide. Thus the total thickness of the camera
when folded up is no greater than necessary to accomodate the requisite supply
of sensitive material.
This expansibility can be obtained in various ways, but I prefer to adopt a
construction comprising two frames placed one within the other so as to form a
double body or telescopic box of rectangular form. The outer frame of the body
forms a box or case to contain the plate holders or other sensitized material
holders, and has a door to permit of their insertion or withdrawal. It may carry
near the front end a ground glass focussing screen, in a frame which fits into
grooves in the sides of the case; the plate holder in use is placed before this,
and those not in use are placed behind it. The back of this case may be closed
entirely if a focussing screen is not used, or if one is used the back of the case
may be provided with an opening, closed with a spring door or doors, and folding
side wings or flaps, all as are well known for focussing hoods.
Inside this case. is placed another, consisting of a frame open back and front.
The outer case or frame telescopes on to this, and is retained in a moveable or
floating position relatively thereto by means of pivoted swing or rocking plates
(which may be provided with teeth to ensure the parts moving in the correct
plane), or with levers, links, or other suitable devices.
The plate holder in the exposing position is kept close up to its proper face on
the inner frame, in the correct focal plane, by suitable springs, and the outer case
is so placed and operated upon by springs that it has always a tendency to expand

page_text: to its maximum limit, being closed to its minimum limit by pressure (say against
the body of the operator), and retained there by spring catches or other suitable
devices.
Within the inner frame or body I place another frame (which I term the
foundation frame), the purpose of which is to connect up and support all the
parts. The baseboard is hinged or pivoted to the bottom edge of this, the struts
or stretchers are pivoted to its two sides, near the top, their outer ends being
pivoted to the baseboard, or to lugs thereon. The bellow's is attached to this frame
in any suitable way, the means I prefer to adopt being to bind it thereto either by
turning over the edges of the frame on to the bellows, or by clamping the bellows
between the foundation frame and another one fitting tightly therein. It will thus
be understood that the baseboard, foundation frame. stretchers, and bellows are
all erected as one complete piece of apparatus. This is attached to the body by
screws or other suitable means which secure the foundation frame in its correct
position inside the inner body.
A carrying bandle may be attached to the outer body, and one or more plates
for the tripod screw may be attached to the foundation frame, or to the inner
body, or to the baseboard.
If desired the foundation frame may be dispensed with and the baseboard,
struts, and bellows attached to the inner body instead. The construction described,
however, is preferred.
In order to ensure an absolutely light joint between the face of the plate
holder and the face of the foundation frame, the latter may be formed with a
recess or well into which the plate holder is pressed by the springs behind. Or a
tongue running completely round the face of the plate holder may fit into a
corresponding groove in the foundation frame; or the groove may be in the plate
holder and the tongue in the frame. All these methods are open to some little
objection, and as this part of most cameras is unsatisfactory I prefer to adopt the
following method. The plate holder slides or drops into a space or groove between
the face of the foundation frame and ribs or other faces on the inner frame of
the body, the groove or space being sufficient to allow it to go in easily. A frame
is so mounted in the opening in the foundation frame as to be projected forward
by the force of springs, and come into contact with the face of the plate holder.
To ensure better contact and effectually exclude light, the face of this frame is
covered with plush, velvet, rubber, or other suitable material which is secured
thereto by turning over the inner or outer edges of the frame to grip and clutch
the plush at its edges, with the centre part raised, the whole resembling the
mounting of the well known Clincher tyre. Thus the plate holder is always held
in the exact focal plane, can be very easily inserted in or removed from the camera,
and light is prevented from entering between the joint, especially when with-
drawing or replacing the covering slide or shutter of the plate holder.
The stretchers may be of the usual form having slots through which are passed
pins attached to the inner frame; or they may be solid, and have pins which slide
in slotted plates attached to the said frame, or in slots in the
frame itself but the form of stretchers I prefer to adopt consists of two solid
links, pivoted together, rule joint fashion, so as to double in two when the
camera is folded. When the camera is erect the links are straight, and their
respective links interlocked by means of springs formed near their knuckle joints.
The front or lens carrier, is pivoted between the upright prongs of a swinging
fork, which in turn is pivoted or hinged to the baseboard, near the front end, and
is held vertically and in line with the fork prongs when erected by springs or
other suitable devices.
This front is made self erecting by connecting links pivoted at one end to the
bottom sections or links of the back stretchers, and at their other ends to the fork
prongs. The result is that when the back is turned up to a right angle with the
baseboard the links turn the front up at the same time also to a right angle to
the baseboard. The motion is assisted, and the parts retained in their proper

page_text: positions, by means of a strong spiral spring mounted on the cross rail of the
front fork.
The front is provided with the usual sliding movements in a vertical and
horizontal direction to vary the position of the lens in relation to the plate, and
any suitable means may be adopted for causing the front to move or swing
backwards or forwards for adjusting the focus of the lens, and to maintain a
parallel motion in relation to the body.
An alternative method of focussing is to mount the lens in a double sliding
jacket or sleeve, which, by means of a lever or pointer working over a marked scale,
can be moved to and fro. The sleeve may form a part of the camera front, the
lever being placed between or on the outside.
The front is made of aluminium turned over at its edges, and the bellows is
secured thereto by a clamping frame which fits tightly in the rim thus formed in
the front. A space is left between the frames to allow free passage of air to or
from the bellows, when opening or closing the camera, but the arrangement is
such that a tortuous passage is formed which will not allow light to pass.
The lugs, to which the front fork and the back stretchers are pivoted, are
stamped up from the baseboard, and the holes thus left may be filled up by plates
or other means.
The edges of the baseboard, body frames, and other parts, are turned over so as
to form strengthening rims which enable very thin metal to be used, and yet secure
the necessary stiffness and strength. To further, stiffen the camera, ribs may
be stamped in the baseboard, body frames, and other parts, which will also improve
the general appearance.
The outside of the two body frames and baseboard may be covered with leather,
which may be cemented thereto, but still further secured by being clamped by
the turned over edges aforesaid.
The inside of the body and baseboard may be finished in any suitable way, or
by any suitable flexible covering, but I prefer to either attach a thin covering of
polished mahogany veneer, or else to print or color the metal in imitation of
that wood.
An exposing shutter of any suitable description may be attached to or built
into the camera front, though I prefer to use a lens having a shutter forming a
part of its mount.
A focussing jacket may form a part of the front, by means of which the lens
(carrying its shutter) is moved to and fro to focus, by means of a lever mounted
in the front, which also indicates the distances upon a scale on the front itself.
The whole of the devices comprising the camera back, including the expanding
arrangements, and spring frame for forming contact with the plate holders, may
be used in cameras of the box form as well as in those of the folding type.
Dated this 10th day of T1000
.
I, JOHN EDWARD THORNTON, of Rokeby, Oldfield Road, Altrincham, in the
County of Chester, Manufacturer, 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:-
-
The improvements forming the subject of this invention relate to the design
and construction of photographic cameras whereby advantages of convenience to
the user and advantages in the manufacture are obtained.

page_text: This invention relates to that class of camera known as folding hand cameras
constructed with a baseboard to one end of which a body or back is hinged and
at the other end the front the body and front being connected by bellows. The
body carries or encloses the sensitive plate or film and the front when the camera
is folded and the front carries the optical system comprising the lens and shutters
and their accessories.
It is designed to provide a hand camera which can accommodate in the body.
one two or three plate holders or a roll holder or a plate magazine as may be
required by the operator, but without the said chamber, and therefore total thick-
ness and bulk of the camera, being any larger than necessary when in use; in
which the front will be self erecting, and in which a light tight joint will be
maintained between the camera and the sensitive plate or the camera for the
same.
The invention consists essentially in constructing the body of the camera with
the back capable of moving or expanding to enlarge the chamber into which the
carrier for the sensitive material is placed so that it may accommodate different
sizes or numbers of such carriers and be closed down to the smallest size necessary,
in constructing the front and stretchers so that on the base board being released
the front will be self erecting, and in holding the carrier in its correct position in
the camera by fixed stops behind the carrier and excluding the light by means of
a movable or yielding spring frame that presses against the face of the carrier.
It will be fully described with reference to the accompanying drawings.
Fig. 1. Is a side elevation partly in section of camera constructed in accordance
with the invention showing the back in its closed or non-expanded position.
Fig. 2. Is a sectional plan of same.
Fig. 3. Is another sectional plan of Fig. 1 showing the back expanded only
sufficiently to accommodate one double plate holder and also inclined to a con-
venient angle to facilitate insertion of the plate holder.
Fig. 4. Is a similar plan to Fig. 3 showing the back expanded further in order
to accommodate a roll holder or two double plate holders.
Fig. 5. Plan showing back expanded to the same extent as Fig. 4 and inclined
to allow of the easy removal and replacement of the roll holder or of the plate
holders.
Fig. 6. Is a side elevation partly in section of camera showing a modified arrange-
ment for operating the expansible back with the back expanded or extended.
Fig. 7. Is a side elevation in section of the arrangement shown in Fig. 6
with the back in its closed position.
Fig. 8 Is a plan of same partly in section with the parts in position as
shown in Fig. 6.
Fig. 9. Is a side elevation partly in section showing another modification of
mechanism for operating the expansible back with the back expanded..
Fig. 10. Is a side elevation of same with the back closed.
Fig 11. Is an elevation in section from the back showing same mechanism as
Figs. 9 and 10.
Fig. 12. Is a side elevation in section showing another modification of expansible
back with the back in its expanded position.
Fig. 13. Is a side elevation of same when closed.
Fig. 14. Is a sectional plan of same when open (Fig. 12).
Fig. 15. Is a sectional plan of same when closed.
Fig 16. Is a side elevation partly in section showing a further modified arrange-
ment for operating the expansible back with the back in closed position to secure
a single plate holder.
Fig. 17. Is a plan of Fig. 16 partly in section.
Fig. 18. Is a side elevation of the camera extended (partly in section) showing
the improved arrangement of stretchers and self erecting mechanism for the
Smant

page_text: "
Fig. 19. Is a side elevation of the camera folded showing the position of the
stretchers self erecting mechanism and the front folded therein.
Fig. 20. Is a plan of Fig 18.
Fig. 21. Is a front elevation; camera extended as in Fig. 18.
Fig. 22. Is a side elevation (partly in section) of the camera extended showing a
modified arrangement of stretchers for erecting the front.
Fig. 23. Is a side elevation of the light excluding frame detached from the
camera.
Fig. 24. Is an elevation, looking from the back towards front of camera with
frame removed to show the position of the actuating springs.
Fig. 25. Is a sectional elevation of Fig. 23.
Fig. 26. Is an enlarged sectional detail.
Fig 27. Is a sectional detail showing a modified form of the spring actuated
frame.
In constructing the camera I prefer to construct the chief parts which are not
subjected to much wear and tear of sheet aluminium the other parts being made
of hard brass. Other materials (including wood) may be used where desirable
but the use of metal permits of great lightness combined with stiffness and
rigidity and also cheapness and accuracy in production.
Referring to Figs. 1 to 17 the construction of the expanding back of the camera
will first be described.
The camera comprises the base A the front B the body D and the bellows C
connecting the front and the body. The base A is hinged to the foundation
frame and the front B is hinged or pivoted to the base A by the uprights a
in the usual way.
.
The body I construct of three parts a rigid frame or case of rectangular form
a second or foundation frame I placed inside the frame or case E and rigidly
attached thereto and a back G capable of sliding to and fro in or on the others
to give the desired size to the compartment' H which receives the carrier of the
sensitive material.
The foundation frame F is rigidly attached to the case E and to it are con-
nected or fixed the several movable or operative parts of the camera. The base
board A is hinged or pivoted to the bottom edge of the foundation frame F, to
which the bellows C are also attached and the stretchers K are also pivoted at
one end to the foundation frame. It will thus be understood that the foundation
frame the base board A the bellows C and the stretchers K are all erected as
one complete piece of apparatus and are then secured in correct position by
means of the foundation frame F in the case E.
The back G with case E forms a double box or case one sliding or telescoping
within the other. The back G forms a box or case to contain the plate holders
or roll holder for flexible material and is open at one side provided with a lid
or door L to permit of their insertion or with-drawal. The door is pivoted at one
edge and provided with a spring to cause it to open when released being held
closed by a catch.
The back G when in its closed position holds one plate holder and when in
its extended or expanded position holds a roll holder or three plate holders which
are about the same size.
The back G may be closed entirely if a focussing screen is not used or if one is
used the back of the case may be provided with an opening, closed with a spring
door or doors and folding side wings or flaps all as are well known for focussing
hoods.
'
In the arrangement shown in Figs. 1 to 5 the back G is provided with a second
inner frame which passes into the interior of the case E. It is supported by a
radial link fand is held in position by a spring catch g¹ attached to the foundation
frame F which engages with a series of notches in the frame g to hold it in the
desired position. At the side next to the aperture it is connected to the foundation
plate by links f f which permit of the one side opening in advance of or beyond

page_text: the other to facilitate the insertion and removal of the holders and of being moved
back into a position square and parallel with the foundation plate F which is
necessary for photographic purposes.
In the arrangement shown in Figs. 6 to 8 the back G slides to and fro over the
case E. To ensure a parallel movement between the two parts I employ two
quadrants M. M connected together by a link m at the bottom of the camera body
engaging with racks N N¹ and two similar quadrants at the top of the camera
body engaging with corresponding racks. The top quadrants are connected to
the bottom ones by uprights m'. The quadrants are pivoted to the foundation
frame For to the case E and the racks are attached to the movable or expansible
back G hence any movement of the quadrants or any movement of the back with
the racks is equally transmitted to all the parts causing a parallel movement of
the back G in relation to the case E and foundation frame F. To give an
automatic movement to the back G when released springs O are applied to one or
more of the quadrants preferably to all four which cause them to move in relation
to the foundation plate E and force the back outwards. The back G when in
its closed position is held against the action of the springs by the hook or catch c
engaging the spring catch e. By depressing the spring catch c¹ the back is
released and springs back into the expanded position.
The spring door L is opened to admit the introduction of the plate holder
or roll holder.
In the arrangement shown in Figs. 9 to 11 I pivot to the foundation plate F
three long fluted rollers or pinions P P1 P2 which engage with racks R R R R*
RR attached to the inner surface of the movable expansible back G. Any
movement of the back G causes the rotation of the pinions in the racks and
ensures an even or parallel movement. The back G is moved in one direction
or the other by the crank or eccentric and the link . The back G is held
in the desired position by the handle or lever p of the eccentric p engaging in
notches ¹.
In the arrangement shown in Figs. 12 to 15 the expansible back G is provided
with slides S and to the foundation frame F are attached corresponding slides or
guides T over which the slides S fit and slide thereby maintaining the back G
parallel with the case E. The back is pressed outwards by the springs s attached
thereto and bearing against the spring blocks s¹ attached to the foundation
frame F. The back G is held in the desired position by the spring catch t
engaging with the notches the catch t being released when required by the
sliding piece T attached to one side of the back G. By pressing down the
sliding piece T the wedge shaped end comes under the end of the catch and
raises it out of the notches t¹ thereby permitting the back to expand under the
action of the springs s.
In the arrangement shown in Figs. 16 and 17 the expansible back G passes
inside the case or frame E from which it is capable of sliding out in a backward
direction and also of swivelling to permit of the more easy insertion of the plate
holder or roll holder. The back G is held in position by the spring latches ggl
one placed at the top and the other at the bottom and attached to the inwardly
projecting sides of the back. A sliding bar U is attached to the foundation plate
or frame with a projection u at one end to engage with the side of or notches
in the spring latches g¹ and at the other end a projecting piece u¹ is attached
for the same purpose. The spring latches are each provided with a notch g2
with which the projections u engage when in the expanded position. The
sliding bar U is moved by a button U extending through the case E which can
be pushed from the outside, it slides along the foundation plate F disengaging
the end u from the latch g and raising the other latch g until it is clear of and
disengaged from the projecting piece u thereby leaving the back G free to swing
into the position shown in dotted lines in Fig. 17. The back is held in its
first or unexpanded position by the pins on the sliding bar V on one side of

page_text: the foundation frame F. The pins
slide in slots in one side or edge of
the back F. When it is desired to expand the back the sliding bar is moved
by the pivoted lever W until the pins are in line with the longitudinal slot v¹
the back G is then drawn out or moved out by a spring into its expanded posi-
tion and is locked again and held in that position by the pins entering the
transverse ends of the slots by the movement of the bar V and lever W.
Referring to Figs. 18 to 22 Sheet 4 the construction of the improved arrange-
ment of stretchers and self erecting front will be described.
The base board A is hinged or pivoted to the foundation frame F¹ of the
body D and the front B is hinged or pivoted to the base board between the two
uprights e being connected to the body D in the usual way by the bellows C.
The front B is pivoted upon the pins or pivots el² and the fork E is pivoted
to the base board A near to the front edge thereof. To the fork E are con-
nected one or two spiral springs F by which the uprights e are raised to an
upright position the strength of the spring being sufficient to lift the fork and
draw outwards the front B when the base board is released from the body D.
The base board A is pivoted to the foundation frame F of the body D and
is also connected to it by stretchers G at both sides the stretchers G at the
two sides being alike. The stretchers G are formed in two parts pivoted
together at or near the centre with a rule joint g so as to fold in two when the
camera is folded. At one end the stretchers G are pivoted to the camera body 1)
and at the other or outer end to the base-board A. When the camera is erect
or extended the stretchers G are straight (see Fig. 18).
A spring ear or catch H is attached to the lower member of each stretcher
and rests upon the edge of the upper member to prevent a folding movement
until they are pressed inwards out of contact with the upper member.
A spring K is placed behind the upper members of the stretcher G to move
it outwards into a straight position.
The uprights e of the front fork E are connected to the lower members of
the stretchers G by links L whereby the fork is moved outwards with the
stretchers the spring F acting at the same time to lift the fork into an upright
position..
The uprights e of the fork E are guided at each side by a second link M
with a pin m traversing a slot m¹ in the upright e. The pin also traverses a
slot n in a bracket N attached to the side of the front B to hold or maintain
the front perfectly vertical when erected.
Each of the links L are preferably pivoted to the stretcher G by means of a
plate or bracket ( adjustably attached to the stretcher by a screw or pin o by.
which the position of the front B can be accurately adjusted for focussing
purposes.
In Fig. 22 the stretcher G is shown attached direct to the fork upright E
by the connecting piece L to maintain the front B in the upright position
when raised by the spring F as before.
.
Referring to Figs. 23 to 27 Sheet 5 the construction of the spring frame
for excluding light from entering the camera around the roll holder or plate
carrier will be described.
A rectangular movable or sliding frame A is fitted inside a second frame
or case B attached to or forming part of the camera body. The frame A is of
any suitable material and cross section but I prefer to make it of sheet metal
of angle form though it may be of channel shape as in Fig. 27. The frame or
case B is also of angle shape. Behind the frame A are placed a number of
springs C which are attached to the frame B and tend to actuate or force the
frame A outwards to keep it in close contact at every point with a plate or
plate carrier placed against it. The frame A is covered with a layer à of soft
pile fabric such as plush.
As the junction of the frame A with the plate or plate holder forms an approxi-

page_text: mately air tight joint it is desirable to form air passages to permit of the ingres
and egress of air consequent upon the opening and closing of the bellows D such
passages being at the same time light tight.
These passages & are formed between the frame or case B and a third frame E
which is separated at intervals from the frame B by pieces e inserted, between.
The junction between. the two frames B and E towards the inner side is covered by
a metallic clip or strip giving a tortuous shape to the air passage
opens into the interior of the two frames A and B (the air passing inwards in
the direction of the arrows) and renders it perfectly light proof.
which
The bellows D are attached to the frame E. The edges of the baseboard body
frames and other parts are turned over so as to form strengthening rims which
enable very thin metal to be used and yet secure the necessary stiffness and
strength.
The outside of the case E back G and baseboard A may be covered with leather
which may be cemented thereto but still further secured by being clamped by
the turned over edges aforesaid.
The inside of the body and baseboard may be finished in any suitable way or by
any suitable flexible covering but I prefer to either attach a thin covering of
polished mahogany veneer, or else to print or color the metal in imitation of
that wood or to attach a veneer of such printed metal.
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 camera constructed with a back capable of expanding or sliding outwards
to enlarge the plate or roll chamber to accommodate different sizes or number
of plates or film carriers substantially as described.
2. A camera constructed with a back arranged to swivel or incline to one side
to enlarge the entrance-either with or without a sliding expanding movement-
to permit of the more easy insertion of the plate or roll carrier substantially as
described.
3. A camera comprising in its construction a base A front B and bellows C
connected together a casing E to which these are connected and a sliding exten-
sible back G movable to and fro in or on the casing E capable of adjustment to
receive one or more holders for the sensitive material or holders of different sizes
substantially as described, with references to Figs. 1 to 17.
4. A camera constructed with a foundation frame F to which the movable or
operative parts of the camera are connected or attached substantially as described.
5. A camera constructed with a foundation frame F to which the base board
and optical apparatus are attached or connected at one side and a sliding movable
or expansible back attached or connected at the other side substantially as and
for the purpose described.
6. A camera constructed with a front pivoted to the base board and con-
trolled or operated by a spring which when the base board is released operates
to draw it down and to erect the front in position for photographing sub-
stantially as described.
7. In a folding camera having a base board A front 13 bellows C and fork E
between which the front is pivoted the combination therewith of a spring
attached thereto to raise the fork into an upright position substantially as
described.
8. In a folding camera the combination with the body D the base board
pivoted thereto the fork E pivoted to the base board the front B pivoted thereto
and the bellows connecting the front and body of the stretchers G and springs K
of two parts pivoted together the links L connecting the fork to the stretchers
the second links M for holding the front vertical and the spring connected to
the fork E to raise the fork and with it the front into a vertical position when
the base board is released substantially as described, with reference to Figs. 18
to 22

page_text: 9. A camera constructed with a light excluding appliance with a movable or
yielding spring frame pressed against the face of the carrier substantially as
described.
10. A camera constructed with a movable and sliding frame and springs
bearing against and actuating the same to form a light tight joint between the
camera and the front face of the plate or of a plate or roll holder substan-
tially as described.
11. A light excluding frame for cameras comprising in its construction a
fixed frame or case a spring actuated frame sliding backwards and forwards
therein and springs inserted between the two frames and pressing against the
face of the carrier substantially as described and shown.
12. In a photographic camera the combination with a fixed frame or case of a
spring actuated frame sliding therein springs inserted therein a third frame
attached to the case by pieces inserted at intervals between them to form air
passages and a metallic strip placed to cover the junction of the two frames and
give a tortuous shape to the air passages substantially as described.
13. A camera constructed substantially as described and shown with reference
to Figs. 1 to 5. Figs. 6 to 7. Fig. 8. Figs. 9 to 11. Figs. 12 to 13. Figs. 14
to 15, or Figs. 16 to 17 of the drawings.
14. A camera constructed with self erecting front and stretchers substan-
tially as described and shown with reference to Figs. 18 to 21 or Fig. 22 of the
drawings.
15. A light excluding frame or appliance for cameras constructed and arranged
substantially as described and shown with reference to Figs. 23 to 27 of the
drawings.
Dated this 15th day OI March 1900.
WM. P. THOMPSON & Co.,
Manchester, Liverpool, & London, Patent Agents.