Improvements in Magazine Cameras.
Year: 1893

page_text: Date of Application, 4th July, 1893—Accepted, 19th Aug., 1893
COMPLETE SPECIFICATION.
Improvements in Magazine Cameras.
A communication from EZRA R. ANDREWS, of 455, Exchange Street, Rochester,
in the State of New York, United States of America. Printer.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent, 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 an improved magazine holder for photographic cameras,
designed to carry either sensitized glass plates or films of any preferred kind, and
to expose the same in succession by a simple, cheap and easily managed mechanism.
This invention is fully described and illustrated in the following Specification and
the accompanying drawings.
The improved magazine holder is represented in the accompanying drawings in
which :-
Figure 1 is a side elevation of a camera with this improved magazine holder
attached thereto.
Figure 2 is a side view of the holder, the sliding door through which the
unexposed plate or films are inserted, being removed.
Figure 3 is a section of the holder on the line 3-3 Figure 5, showing the parts
above that line.
Figure 4 represents the follower frame detached.
Figure 5 is a front view of the holder, showing a portion of a plate or film in
position for exposure.
Figure 6 is a section of the holder on the line 6-6 Figure 5, showing the parts
to the right of said line.
Figure 7 is a rear elevation of the holder.
Figure 8 represents one of the feed-screws detached.
Figure 9 is a section through the operating crank or lever on the line 9-9
Figure 7.
Figure 10 represents the front end of one of the feed-screws.
This improved holder may be applied to any suitable camera.
In the drawings
A Figure 1 represents the body of the camera, which may be of any suitable or
preferred construction, provided with a lens B and any suitable focussing mechanism
and exposing shutter. C is the holder which is attached to the rear of the body by
the usual rabbeted or light tight joint, and is provided with the door D at one side
through which the unexposed plates are inserted into the magazine. The holder
is detachably connected with the body, by any suitable hinges or catches F
Figure 1.
The plates or films in the improved holder are fed forward one after the other
into the position for exposure by turning a crank or lever G Figure 7 on the rear
end of the holder, a suitable septum being interposed between each negative
sheet, and a series of screws and a follower being employed to carry the sheets
forward to the focussing plane. It will be understood that when films or flexible
supports for the sensitive material are employed, they are provided with suitable
carriers. After the sheets for the production of negatives have been exposed, one
after the other, they are deposited in a receptacle E in the lower part of the
camera in front of the holder.
The mechanism for advancing the plates or films consists of a series of screws a a a
arranged parallel with each other at suitable distances apart within the holder and
connected together so as to rotate simultaneously. In the construction shown, the

page_text: screws are arranged to be rotated at the same time by means of the gear H, which
meshes with the pinions on the rear ends of the screws. The handle or crank G
is attached to the rear end of one of the screws so that by turning it the screws
through the gear H are all caused to rotate. The gear revolves on a suitable
stud inserted in the back of the holder. The rear ends of the screws revolve in
suitable journals in the back, their front ends being supported in holes in the
bars c c
Figures 5 and 6 attached to the plates d and fat the front of the holder.
It will be understood that the distance between the bars c c corresponds with
the width of the plates or carriers which the holder is designed to carry, a slight
allowance being made for clearance. At their forward ends the screws are
provided with the enlarged spiral threads e of a diameter sufficient to project over
and engage with the edges of the plates or carriers. These threads extend around
the screw about one and one-half turns, so that as they revolve, their outer ends
discharge the foremost plate or carrier, while their inner ends engage with the next
plate and move it forward into the focal plane. In order to cause the plates to
engage with the inner ends of the enlarged screw-threads, it is necessary to urge
them forward constantly, and this is accomplished by the follower I, carried by the
screws a and arranged to bear on the rear plate through a suitable interposed
spring or cushion. In the construction shown the follower I consists of the crossed
bars 9 g attached together at the point where they cross, and provided at their
ends with perforated bosses threaded to receive the screws a. A spring or
springs may be interposed between the follower and the rear one of the unexposed
plates, J Figure 6 in any suitable manner. This is conveniently effected by
attaching the springs i to the bars g g¹. Any other suitable arrangement of the
follower or spring may be adopted.
In Figures 5 and 6 the foremost plate or film is indicated at L in position for
exposure. At this time its edges are engaged with the threads e on the forward
end of the screws a and the crank G is arrested by a stop k which arrests its motion
at the position when the foremost film occupies the focal plane. The operator
knows that when the crank G is arrested by the stop the foremost plate is in the
focal plane, ready for exposure. A spring or detent Figure 9 attached to the
crank comes in contact with the stop k. When it is desired to turn the crank,
the detent is moved out of contact with the stop by pressure on the bottom m.
A spring n keeps the detent normally in position to come against the stop as the
crank revolves. The detent is attached to the hub of the crank in such way as to
permit the requisite movement. Any other suitable means may be employed for
arresting the rotation of the crank at the proper point.
The
Suitable ways or guides ppl are employed to keep the plates or carriers in the proper
position as they are urged forward by the follower and engaged by the threads e e.
The guides ppl are attached to the sliding door D so that they are removed when
the door is taken out to load the magazine with unexposed plates or films.
door is fitted into the holder light-tight, and, when the holder is detached from the
body of the camera the door is readily removed by sliding it edgeways out 'of
the grooves in the wall of the holder.
It will be understood that the threads e are bevelled on their ends, so that they
may readily enter between the carriers and separate them from each other. In
Figure 5 the film or carrier L is shown as partially broken away, to display the
parts behind it.
The lead or pitch of the screws on the larger threaded sections is greater than
the lead on the smaller sections, a proportion which has been found to work
satisfactorily in practical use being two to one.
A counter consisting of two differential gears r and s Figure 7 may be applied to
one of the feed-screws.
This improved camera is simple and cheap in construction and entirely reliable
in practical use.
The threads e may be made of any suitable length adapted to hold the 'films or
plates.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondent, and in what manner the
same is to be performed, I declare that what I claim is
--
1. The combination in a magazine holder of a series of parallel screws having
short threaded sections of greater diameter at their forward ends the lead of the
screws on the larger threaded sections being greater than the lead of the screws on
the smaller threaded sections means for revolving the screws simultaneously a
follower threaded on the screws and provided with a spring or springs whereby the
unexposed films or carriers are pressed forward to engage with the enlarged
threaded sections substantially as described.
2. The combination in a magazine holder of a series of parallel screws having
short threaded sections of greater diameter at their forward ends the lead of the
screws on the larger threaded sections being greater than the lead of the screws on
the smaller threaded sections means for revolving the screws simultaneously a
follower provided with a spring threaded on the screws and a door arranged at one
side of the holder to permit the insertion of the films or carriers between the
follower and the enlarged sections, substantially as described.
3. The combination in a magazine holder of the screws a a a a provided with
enlarged threaded sections e and pinions 6 the gear H and the follower I consisting
of bars g g and provided with the springs i substantially as described.
4. The combination in a magazine-holder of a series of screws a having enlarged
threaded sections e and connected to rotate simultaneously the follower I provided
with a spring or springs and fitted to the screws a and the plates d and carrying
bars c substantially as described.
5. The combination in a magazine-holder of a series of screws a having enlarged
threaded sections e and connected to rotate simultaneously the follower I provided
with a spring or springs the guides p and the door D carrying guides 'p¹ substantially
as described.
D
11
201 1
1000
W. P. THOMPSON & BOULT,
London, Nottingham, Liverpool, and Manchester, Agents for the Applicant.