Improvements in D Mechanism for Actuating such Shutters.
Year: 1887

page_text: Date of Application, 8th Sept., 1887
Complete Left. 8th June, 1888
Complete Accepted, 13th July, 1888
Improvements in D
Mechanism for Actuating such Shutters.
I ARTHUR SAMUEL NEWMAN of 87 Evershot Road Finsbury Park in the County
of Middlesex Electrician do hereby declare the nature of this invention to be
as follows:-
-
This invention relates to improvements in shutters for photographic cameras and in
the means or method of actuating the same and has for its object to provide a shutter
working inside the camera (i.e. between the back of the lens and the focussing screen
work though also
or sensitive plate) being more particularly adapted for "studio"
advantageous for "amateur" and other uses.
This improved shutter is made in two parts or flaps which open inwardly on upright
hinges or pins mounted vertically at each side of the shutters being arranged somewhat
after the manner of a double casement window and where the edges of same meet in
the middle they are formed so that in shutting they overlap or intersect one another so
as to make a light-tight joint and in addition are lined or padded at such joint and
also at the top and bottom with velvet or other suitable light-tight material so as to
ensure a light-tight fitting all round-the hinges being advantageously placed behind
projecting flanges or framework mounted all round the opening.
This "casement" shutter is actuated by a pneumatic cylinder and loose piston
therein actuated by the operator with an india-rubber or other suitable compression
ball and tube.
One end of the cylinder is open and a rod is mounted on the piston at one end
and sliding in an eye or bearing at its other end and so serving as a guide.
On the piston (or it may be on this guiding rod) a second rod is mounted and this
is the actuating rod which at its other end is connected to a crank arm on one of the
shutter hinge pins which it thus rotates and so opens and closes one flap or part of the
shutter.
On the head or top of this hinge pin is mounted a circular disc or other suitable
contrivance having two upright pins or projections mounted thereon and a corresponding
contrivance on the head of the hinge of the other flap or half shutter.

page_text: Those projecting pins are connected together crosswise that is to say the connecting
rods (which may advantageously be made of piano-forte wire) cross one another in their
path and in one (or both) of these a spring (or springs) is inserted and thus the two
flaps or half shutters move simultaneously together while the spring causes them to
close tightly or when opened to lay right back.
The details may be varied as for instance the flaps or half shutters may be mounted
horizontally instead of vertically as described or the air cylinder may be mounted
above instead of below the shutter.
TONGUE & BIRKBECK,
34, Southampton Buildings, London, W.C.,
Agents for the Patentee.

page_text: Mechanism for Actuating such Shutters.
I ARTHUR SAMUEL NEWMAN of 36 Wray Crescent Finsbury Park in the County
of Middlesex Electrician 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 improvements in shutters for photographic cameras and in
the means or method of actuating the same and has for its object to provide a shutter
advantageously for working inside the camera i.e. between the back of the lens and the
focussing screen or sensitive plate being more particularly adapted for studio work
though also advantageous for "amateur and other uses.
This improved shutter is made in two parts or flaps which open inwardly on upright
hinges or pins mounted vertically at each side of the flaps forming the shutter being
arranged somewhat after the manner of a double casement window and where the
edges of same meet in the middle they are formed so that in shutting they overlap or
intersect one another so as to make a light tight joint and in addition are lined or
padded at such joint and also at the top and bottom with velvet or other suitable
light tight material so as to ensure a light tight fitting all round the hinges being
advantageously placed behind projecting flanges or framework mounted all round the
opening.
This "casement shutter" is actuated by a pneumatic cylinder and loose piston therein
actuated by the operator with an india rubber compression ball and tube or other
suitable apparatus.
One end of the cylinder is open and a rod is mounted on the piston at one end and
sliding in an eye or bearing at its other end and so serving as a guide.
On the piston (or it may be on this guiding rod) a second rod is mounted and this
is the actuating rod which at its other end is connected to a crank arm on one of the
shutter binge pins which it thus partly rotates backward and forward and so opens
and closes one flap or part of the shutter.
On the head or top of this hinge pin is mounted a circular disc having two upright
pins or projections mounted thereon, or other suitable contrivance such as a crank
arm, and a corresponding contrivance on the head of the hinge of the other flap or half
shutter.
These projecting pins are connected together crosswise that is to say the connecting
rods (which may advantageously be made of pianoforte wire) cross one another in
their path and in one (or both) of these a spring (or springs) is inserted or a single
connecting wire and spring where crank arms are used and thus the two flaps or half
shutters move simultaneously together while the spring causes them to close tightly or
when opened to lay right back.

page_text: The details may be varied as for instance the flaps or half shutters may be mounted
horizontally instead of vertically as described or the air cylinder may he mounted
above instead of below the shutter.
And in order that my invention may be easily understood and readily carried into
practice I will now proceed to more fully describe the same with reference to the 5
accompanying drawings.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is an exterior view in elevation of my improved shutter and apparatus
looking from inside the camera the shutter being closed.
Figure 2 is a similar view with shutter open and the pneumatic cylinder shown in
section.
Figure 3 is a plan of the apparatus.
Figure 4 is a sectional plan of Figure 2 on line 1-1 and,
Figure 5 also is a sectional plan of Figure 2 on line 2-2.
a bare the two flaps of this casement shutter mounted on axes a¹ 61 respectively
which axes have at each end thereof cranks or lever arms c d e f the two former
and two latter being set at particular angles to each other especially c and d their
positions being such that when the flaps are either closed as in Figure 1 or wide open
as in Figure 2 the pins el d¹ are nearer to each other than when the flaps a bare half
open the consequence is that the spring a will act (as soon as the cranks are moved
over the dead centre i.e. when the pull of the spring is equal on each crank) to
either fully open or close the flaps as the case may be and there retain them.
9 is a pneumatic cylinder having a piston g¹ therein which is actuated in the usual
manner from the air tube g³.
On the outer side of g¹ is mounted a piston rod g³ which travels freely through the
bearing and thus serves as a guiding rod.
On this piston rod g³ is mounted the connecting rod e¹ which at its other end is secured
to the pine on the outer end of the crank e. This crank e is also connected at e* to
the crank fat fx by the connecting rod h.
ii are stops on either side to prevent the flaps a b going too far back.
jis the frame carrying the apparatus and kk (Figure 4) are the sides of the aperture
frame which the flaps ab close the top o and bottom p of the aperture frame being a
little deeper and the inner edge of bat (Figure 4) where it overlaps a is lined
with velvet or other suitable material-also the parts m m Figure 2 are similarly
lined or padded so as to make light tight joints.
The operation is as follows:-
The shutter flaps a and b being closed to give an exposure it is only necessary to
send air under pressure (by compressing an india rubber ball or other suitable
contrivance) into the cylinder g behind the piston g¹ this forces the piston and its
rod g along and so by means of the connecting rod e¹ partly rotates the crank e on
the axis a¹.
This crank e being connected by rod h to crank f on axis b' (the relative positions
of these cranks to one another being clearly shown in Figure 5 and also their
relative positions to the top cranks c and d being shown in dotted lines in Figure 3)
causes both axes a¹ and bf to partly revolve simultaneously and so opens the flaps a
and b, immediately the pressure is released & a vacuum thereby created they will
close again so that an instantaneous exposure can thus be given.
If on the other hand a long exposure is required or it is desired to keep the
shutter open for focussing or other purposes this can be done by putting on the air
pressure suddenly as before and letting it leak off slowly-and the spring will then
act to keep the flaps open against the stop i, i.
To close the shutter it is only necessary to create a vacuum behind the piston g
and it will then draw back and so through the connecting rod e¹ cause the flaps to be
closed.
This shutter may be mounted in any suitable or convenient manner within or on

page_text: the camera or other part of a photographic apparatus to which it can or may be
applied.
This method of actuating photographic shutters by means of a pneumatic cylinder
with a loose fitting or "leaky" piston therein is an important feature of my present
invention as by using such "leaky" piston the apparatus can be made cheaply (tight
and accurate fitting not being required) and it does not easily get out of order as with
other pneumatically actuated shutters by clogging with dirt want of oil (no oil being
required) etcetera, the "leaky" piston serving a special purpose in the action of the
apparatus as before described and this pneumatic cylinder and piston acting in com-
bination and in conjunction with the spring or any equivalent spring or springs (for
the purpose of keeping the shutter from opening when it is desired to keep it closed
and keeping it from closing when it is desired to keep it open) is a new feature
in apparatus of this description and together constitute one of the main features of my
present invention.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:-
1. In photographic shutters the flaps a and b mounted respectively on axes a¹ and 6¹
on the top ends of which are crank arms such as c and d and at the other ends e and f
respectively and connected by connecting rod h and spring a respectively and actuated
by a pneumatic apparatus the several parts being arranged and acting in the
manner and for the purposes hereinbefore described and represented by the drawings
hereunto annexed.
2. The arrangement of the cranks c and d at the relative angles shown and of the
cranks e and at the relative angles shown and also at the relative angles to each
other as shown at Figure 3 and in combination with the spring and connecting
rod h substantially in the manner and for the purposes hereinbefore described and
represented in the drawings hereunto annexed.
"
3. In photographic shutters the improved method of actuating the same by means
of a pneumatic cylinder with a "leaky or loose fitting piston therein acting in
conjunction with a spring such as or equivalent to x arranged to act as and for the
purposes hereinbefore set forth.
4. The improved arrangement and construction of photographic shutters sub-
stantially in the manner and for the purposes hereinbefore described and represented
in the drawings hereto annexed.
T: 0L
CT 1000