Improvements in Plate Holding and Changing Devices for Cameras.
Year: 1895

page_text: Date of Application, 7th Dec., 1895
PROVISIONAL SPECIFICATION.
Improvements in Plate Holding and Changing Devices for Cameras.
1, GEORGE WILLIAM MITCHAM of 1 Albert Terrace, Avenue Road, Hampton
in the County of Middlesex, Camera Maker, do hereby declare the nature of this.
invention to be as follows:-
This invention relates principally to that form of magazine photographic cameras
in which the sensitive plates held in carriers are fitted loosely into grooves and
permitted to fall consecutively from one part of the camera to another while
maintaining their parallelism so that each plate may be successively brought into
position for exposure and afterwards moved rearwards to give place to the next
plate until the whole number of the plates has been exposed.
According to this invention the magazine is made detachable from the camera.
and is inserted therein and made to slide back 'or. forth in the interior of the
camera for instance by rack and pinion gear. The magazine consists of a box
open above and open at the front and back for the lower half of the box. In the
inner faces of the two sides of this box are parallel grooves usually thirteen in
number extending from top to bottom of the box. These are intended to receive
the plate carriers the rearmost groove being intended to receive a focussing screen.
The magazine is slightly greater than twice the height of the plate carriers.
Crossing the aforesaid grooves midway of their length is a horizontal groove on
each side of the interior of the magazine and in these two grooves there is fitted a.
sliding panel which when fully pushed into the magazine divides the latter into..
two compartments. At the outer front end of this panel is a suitable catch or
catches and in the camera at the necessary place is a corresponding spring or other
catch or catches to engage automatically with the former catch or catches when
the magazine is pushed from the rear into the camera and moved to its foremost
position. The position of these catches is such that when engaged the rear edge
of the panel corresponds to the fixed or standard focus; variation being had if:
desired by movement of the lens.
The magazine is charged as follows; The focussing screen is dropped into the
rearmost groove and falls to the bottom of the groove. Over it in the same groove.
is inserted a filling piece of wood or other material to prevent the focussing.screen
from falling when the camera is reversed. The sliding panel, which on removal of
the magazine from the camera will have been retained in the camera by the
catches, is released from the catches and slid into its horizontal grooves in the
magazine up to the focussing screen; the sensitive plates in their holders or carriers
are then inserted in the grooves in the upper part of the magazine and rest upon
the panel. The magazine is then slid into the camera and racked to the front
until the catches are heard to engage. The back of the camera is then closed:
A door is made in the back for focussing purposes..
On racking back the magazine the plates will fall one by one into the exposure.
position. Focussing may be done at any time by reversing the camera when the.
exposed plates. will fall back again while the screen, cannot fall back, the number
on the indicator of exposed plates is noted and the magazine is then racked forward.
until, the screen touches the sliding panel. The screen is thus brought to the
exposure position while the plates are all guarded by the panel. The door at the
back may then be opened and focussing performed. by movement of the lens!
The door is then closed and the magazine again racked back until all the exposedu

page_text: plates have resumed their lower position together with the plate next to be
exposed. A back turn of the racking pinion will bring the latter firmly against
the end of the panel.
Dated this 7th day of December 1895
HERBERT HADDAN & Co.,
Agents to Applicant.
Improvements in Plate Holding and Changing Devices for Cameras.
I, GEORGE WILLIAM MITCHAM, of 1 Albert Terrace, Avenue Road, Hampton,
in the County of Middlesex, Camera Maker, 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 principally to that form of magazine photographic cameras
in which the sensitive plates held in carriers are fitted loosely into grooves and
permitted to fall consecutively from one part of the camera to another while main-
taining their parallelism so that each plate may be successively brought into
position for exposure and afterwards moved rearwards to give place to the next
plate until the whole number of the plates has been exposed.
The annexed drawing is a section of so much of the camera as is necessary for
explanation of this invention.
According to this invention the magazine A is made detachable from the
camera B and is inserted therein and made to slide back or forth in the interior of
the camera, for instance by rack and pinion gear C. The magazine consists of a
box open above at a and open at the front at 6 for the lower half of the box and
having in the lower half of the back a focussing screen at c. In the inner faces of
the two sides of this box are parallel grooves d usually twelve in number extending
from top to bottom of the box. These are intended to receive the plate carriers D.
The magazine is slightly less than twice the height of the plate carriers.
Crossing the aforesaid grooves d midway of their length is a horizontal groove e
on each side of the interior of the magazine and in these two grooves there is fitted
a sliding panel E which when fully pushed into the magazine divides the latter into
two compartments.
At the outer front end of this panel is a suitable catch or catches F and in
the camera at the necessary place is a corresponding spring or other catch or
catches G to engage automatically with the former catch or catches F when the
magazine is pushed from the rear into the camera and moved to its foremost
position. The position of these catches is such that when engaged the rear edge of
the panel corresponds to the fixed or standard focus, variation being had if desired
by movements of the lens fitted at f.
The magazine is charged as follows:-After opening the back g of the camera
and removal of the magazine the sliding panel E which on removal of the magazine
from the camera will have been retained in the camera by the catches F G, is
released from the catches and slid into its horizontal grooves e in the magazine ;
the sensitive plates in their holders or carriers D are then inserted in the grooves d
in the upper part of the magazine and rest upon the panel E.
The magazine is then slid into the camera and racked to the front until the
catches F G are heard to engage.
The back g of the camera is then closed. A door h is made in the back g for
focussing purposes.
On racking back the magazine the plates will fall one by one into the exposure
position. Focussing may be done at any time by reversing the camera when the

page_text: exposed plates will fall back again, the number on the indicator of exposed plates
is noted and the magazine is then fully racked forward. The screen is thus
brought to the exposure position while the plates are all guarded by the panel.
The door at the back may then be opened and focussing performed by movement
of the lens. The door is then closed and the magazine again racked back until all
the exposed plates have resumed their lower position together with the plate next
to be exposed. A back turn of the racking pinion will bring the latter firmly
against the end of the panel.
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. The construction comprising the removable magazine with removable central.
dividing panel attachable in the camera substantially as set forth.
2. The construction comprising the removable magazine and dividing panel with.
means for focussing substantially in the manner herein set forth.
Dated this 7th day of September 1896.
HERBERT HADDAN & Co.,
18 Buckingham Street, Strand, London, W.C., Agents to Applicant.