Improvements in Cameras.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in Cameras.
I WALTER GRIFFITHS of Highgate Square Birmingham in the County of
Warwick Manufacturer do hereby declare the nature of this invention to be
as follows:-
My invention has for its object improvements in cameras and refers particularly
to magazine hand cameras, although it is applicable to cameras of all kinds. By
my improvements I provide an instantaneous shutter which is capable of adjustment
so as to vary the instantaneous amount of the exposures in addition to which my.
shutter may be so adjusted as to give time exposures the whole being a most compact
and simple arrangement unlikely to get out of order and easy to manipulate and
adjust. In carrying my invention into effect I mount a circular revolving disc
shutter on the inside of the front casing of the camera which shutter is provided
with an aperture for allowing the exposure when rotated past the opening opposite
the lens. Upon the centre pin upon which this shutter revolves a sleeve is mounted
to revolve independently of the shutter in one direction but is provided with a
flange having a notch which engages with a spring pawl which is attached to the
disc so that as the sleeve revolves in the reverse direction the disc revolves with it.
Adjacent to the shutter a drum is mounted to revolve also on the casing of the
camera, and contains a spiral spring so attached as to have a constant tendency to
revolve the said drum in one direction.
The drum is connected with the aforementioned sleeve by two cords having
reverse actions and each being attached respectively to the drum and sleevc.
The spindle of the drum passes through the casing to the outside of the camera
where it is provided with a lever finger by which the said spring may be wound up
to the extent of one revolution. A stud is formed upon the disc which stud engages
with one arm of a pivoted lever having an actuating arm projecting through to the
outside of the camera for operation by the hand. A wire spring is caused to bear
on the edge of the disc to prevent any backward movement during the time the
spring and sleeve are being set.
The spring in the barrel is first set by being slightly wound up, a stop to the
outside lever being provided to prevent it from becoming totally unwound. An
indicating disc is provided around the outside lever shewing the amount of exposure
at the various points on its circumference. The relative sizes of the drum and
sleeve are adjusted for the sleeve to take four revolutions to one of the lever in
which case four exposures of varying length of time may be taken but I do not
confine myself to this as the nun:ber of varying exposures may be increased or
diminished by
an alteration of the relative sizes of the drum.and 'sleeve. After
being released the disc revolves until the stud engages with a.second arm on the
lever which it passes immediately the actuating arm is released, being then stopped
by the first arm ready for the next exposure. The action of exposure is as follows..
Supposing the spring when wound by the lever to its full extent is strong enough to
revolve the shutter sufficiently quick to give the ordinary instantaneous exposure
and it is desired to have an exposure of a greater length of time the finger would
be set round the dial proportionally to the requirement by which the spring would
only be wound up to a certain extent and consequently would be of less strength so

page_text: that upon the release of the disc by the lever the drum and sleeve would carry the
aperture of the disc past the lens slower as may be arranged by the position of the
finger and the consequent strength of the spring. For the purpose of obtaining
time exposures I carry the pin upon which the actuating lever is pivoted through
the casing to the outside of the camera where it is fixed on a pivoted arm in such a
manner that the pin has a travel which so moves the centre of the actuating lever
as to place the second or stop arm in position to engage with a second or time stud
which is provided on the shutter so as to take effect when the actuating lever is
operated. The shutter thus remains opposite the lens until the actuating arm is
pressed by hand upon which the shutter flies round until the second or time stud
engages with the point of the second arm and retains the aperture of the shutter
opposite the lens until the actuating arm is released and the shutter flies round
and is stopped by the first stud as it engages with the second arm ready for
the next exposure. The second arm is hollowed out to allow the first stud to
pass under it when pressed forward into position for its point to catch the
second stud.
I may apply a similar arrangement to cameras in a cheaper form by having
the revolving disc actuated by elastic in lieu of a spring and having say four
lens to the camera arranged around the disc the aperture of which would pass
each lens in succession being stopped by a catch as before described between
each lens.
Dated this 23rd day of June 1896.
WALTER GRIFFITHS.
COMPLETE SPECIFICATION.
Improvements in Cameras..
I WALTER GRIFFITHS of Highgate Square Moseley Road Birmingham in the
County of Warwick 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 :-
My invention has for its object "Improvements in cameras" and refers
particularly to magazine hand cameras although it is applicable to cameras of all
kinds. By my improvement I provide an instantaneous shutter which is capable of
adjustment so as to vary the instantaneous amount of the exposures in addition to
which my shutter may be so adjusted as to give time exposures the whole being a
most compact and simple arrangement unlikely to get out of order and easy to
manipulate and adjust.
In order that my invention may be clearly understood & more easily carried into
practise I have appended a sheet of drawings illustrating my invention together
with a modification of the same.
Figure 1 is a view of the interior of the lens end of the camera
Figure 2 is a view of the exterior.
Figure 3 is a view shewing a modification.
In carrying my invention into effect I mount a circular revolving disc shutter A on
the inside of the front casing B of the camera which shutter is provided with an
aperture a for allowing the exposure, when rotated past the opening opposite the
lens N. Upon the centre pin upon which this shutter revolves the sleeve C is mounted,
to revolve independently, of the shutter in one direction, but is provided with the
flange c¹, having a notch c³, which engages with a spring pawl a² which is attached to
the disc A so that as the sleeve Crevolves in the reverse direction the dis: A revolves
with it. Adjacent to the shutter A the drum F is mounted to revolve also on the
casing of the camera, and contains a spiral spring so attached as to have a constant

page_text: tendency to revolve the said drum in the direction of the arrow.
The drum may bo
connected with the aforementioned sleeve C by two cords H and H' having reverse
actions and each being attached respectively to the drum F and sleeve C.
.:
The spindle of the drum passes through the casing to the outside of the camera
where it is provided with the lever finger J by which the said spring may be wound
up to the extent of one revolution.
The stud a is formed upon the disc A which stud engages with the one arm k¹ of
the pivoted lever K having also an actuating arm 2 projecting through to the
outside of the camera for operation by the hand. A wire spring L is caused to bear
on the edge of the disc to prevent any backward movement during the time the
drum spring and sleeve Care being set by the hand J. The spring in the drum F
is first set by being slightly wound up the stop to the outside lever being provided
to prevent it from becoming totally unwound. The indicating disc M is provided around
the outside lever shewing the amount of exposure at the various points on its circum-
ference. The relative sizes of the drum F and sleeve Care adjusted for the sleeve
to take four revolutions to one of the lever J in which case four exposures of varying
length of time may be. taken but I do not confine myself to this, as the number
of varying exposures may be increased or diminished by an alteration of the relative
sizes of the drum and sleeve. After being released the disc A revolves until the
stud engages with the second arm k on the lever K, which it passes immediately the
actuating arm k is released. being then stopped by the first arm k ready for the next
exposure. The action of exposure is as follows. Supposing the drum spring when
wound by the finger or lever J to its full extent is strong enough to revolve the
shutter A sufficiently quick to give the ordinary instantaneous exposure, and it is
desired to have an exposure of a greater length of time the finger J would be set
round the dial M proportionately to the requirement by which the spring would only
be wound up to a certain extent and consequently would be of less strength, so that
upon the release of the disc A by the lever K the drum and sleeve would carry the
aperture a' of the disc past the lens slower, as may be arranged by the position of the
finger and the consequent strength of the spring. For the purpose of obtaining time
exposures I carry the pin kupon which the actuating lever K is pivoted, through the
casing to the outside of the camera where it is fixed on an arm k pivoted at kin
such a manner that the position of the pin is capable of being so moved as to
bring the second or stop arm into position to engage with the second or time
stud a which is provided on the shutter so as to take effect, when the actuating lever
is operated. The shutter thus remains opposite the lens until the actuating arm k² is
pressed by hand, upon which the shutter A flies round until the second or time stud a
engages with the point of the second arm 3 and retains the aperture a¹ of the shutter
opposite the lens until the actuating arm 2 is released and the shutter flies round and
is stopped by the first stud a³ as it engages with the second arm k³ ready for the next
exposure. The second arm k³ is hollowed out or raised at k' to allow the first stud a³
to pass under it when pressed forward into position for its point to catch the second
stud. In place of the cords for connecting the spring & disc I may have toothed
wheels F&C as shewn by Figure 3, and I may apply a similar arrangement to
cameras in a cheaper form by having the revolving disc actuated by elastic in lieu of
a spring and, having, say, four lens to the camera arranged around the disc the
aperture of which would pass each lens in succession being stopped by a catch as before
described between each lens.
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
1st. The improvements in cameras substantially as & for the purpose herein set
forth and shewn upon the accompanying drawings.
2nd. The lever K mounted on the movable pivot 4 for the purpose of obtaining
either instantaneous or time exposures substantially as herein set forth and shewn.
3rd. The combination of the spiral spring arrangement F revolving sleeve C and

page_text: disc A actuated as shewn for obtaining varying, degrees of instantaneous exposures
substantially as shewn & described.
4th. The arrangement by which the adjustment for the required periods of
instantaneous exposure winds up the spring for actuating the shutter to the required
extent substantially as herein set forth & shewn.
Dated this 21th day of March 1897
WALTER GRIFFITHS.