OPENING AND SHUTTING THE LENSES OF PHOTOGRAPHIC APPARATUS
Year: 1886

page_text: I, FREDERICK COLLINGHAM MOORE 3 Trinity Court Trinity St. Leeds,
Mathematical Instrument Maker do hereby declare the nature of my invention
for OPENING AND SHUTTING THE LENSES OF PHOTOGRAPHIC APPARATUS to be as
follows:-
My improvements refer to the Photographic Shutter known as the “Flap and
Drop" Shutter.
I retain the flap in position when closed, by means of a stop or catch attached
to the bottom of the dropper, the dropper being held in position by a small pin in
the dropper coming in contact with a piston arrangement fixed to the upper side of
the shutter frame, which piston being withdrawn by pneumatic pressure, allows the
dropper to fall thereby releasing the flap. The flap is now raised by an elastic
band passed round the spindle attached to it, thereby exposing the object to be
photographed. The drop is now held in position by a second pin a little to the
right and above the pin already referred to, which in its turn comes in contact
with the piston; this enables the exposure to be continued the desired length of
time, when this time has expired the action of the piston is reversed, allowing the
second pin to pass by the piston by means of a recess formed in the piston-The
dropper now falls and closes the lens.
In order to make the exposure rapid the second pin is made to move into a line
immediatly behind the first pin thereby not coming in contact with the piston, so
that the fall of the dropper is almost simultaneous with the rising of the flap.
In order to prevent the vibration caused by the sudden raising of the flap, a
diagonal or shaped spring, fixed to the shutter frame, gradually engages the
flap, bringing it to a state of rest without vibration or shock.
The motive power for working the piston is obtained by a small cylinder with a
spring piston which is held in the band of the operator and pressed by the thumb,
this cylinder is connected to the piston fixed on the frame of the shutter by means
of a small flexible tube.

page_text: I, FREDERIO COLLINGHAM MOORE, 3 Trinity Court, Trinity St. Leeds, Instrument
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 :-
My improvements refer to the Photographic Shutter known as the "Flap and
Drop Shutter, and are as follows:-
I retain the flap A in position when closed, by means of a stop or catch B
attached to the bottom of the dropper C; the dropper being held in position by a
small pin D in the dropper coming in contact with a piston E fixed to the upper
side of the shutter frame F, which piston being withdrawn by pneumatic pressure,
allows the dropper C to fall thereby releasing the flap A. The flap A is now
raised by an elastic band G passed round the spindle H attached to it, thereby
exposing the object to be photographed. The dropper C is now held in position
by a second pin I a little to the right and above the pin D already referred to,
which in its turn comes in contact with the piston E, this enables the exposure to
be continued the desired length of time, when this time has expired the action of
the piston E is reversed allowing the second pin I to pass by the piston E by
means of a recess J formed in the piston. The dropper now falls and closes
the lens.
In order to make the exposure rapid the second pin I is made to move into a
line immediatly behind the first pin D thereby not coming in contact with the
piston E, so that the fall of the dropper C is almost simultaneous with the rising
of the flap.
In order to prevent the vibration caused by the sudden raising of the flap a
diagonal or V shaped spring K, fixed to the shutter frame F gradually engages the
flap A bringing it to a state of rest without vibration or shock.
To prevent the dropper C from rebounding after it has fallen and closed the
aperture a spring L is attached to it-In the descent of the dropper this spring
passes under and locks itself against the spindle H.
The motive power for working the piston E is obtained by a small cylinder M
with a spring piston N which is held in the hand, and pressed by the thumb of the
operator This cylinder is connected to the piston E fixed on the shutter frame F
by means of a flexible tube O.

page_text: Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is :-
1st. The stop or catch B.
2nd. The fixed pin D.
3rd. The movable pin I.
4th. The piston E recessed in the manner described in drawings.
5th. The diagonal or V shaped spring K.
6th. The retaining spring L for preventing the rebound of the dropper.
T
1
1000
Witness,
H. CROWTHER,
197, Park Lane, Leeds.
FREDERIC COLLINGHAM MOORE,