Year: 1888

page_text: Date of Application, 3rd May, 1888
"
Complete Specification Left, 4th Feb., 1889
Complete Specification Accepted, 3rd May, 1889
I, HARRY WILLIAMSON TEED, of 188 Camberwell Grove, Camberwell, Surrey,
Civil Engineer do hereby declare the nature of this invention to be as follows:-
My invention relates to shutters for photographic cameras and the like, and to
mechanism for actuating the same.
According to one part of my said invention I provide a shutter for a photographic
camera by means of which, the amount of exposure given to the sensitive plate or
film, or any part of it, can be easily and expeditiously regulated.
My said invention comprises moreover various other improvements hereinafter set
forth.
In carrying my said invention into practice I prefer to provide a shutter formed in
two parts or portions, that is to say divided vertically in the centre of the same
the said shutter may be of a circular or other suitable form when closed and is
provided with any suitable joint where the two parts of the said shutter meet so as to
exclude the passage of light through the same. I provide moreover the said shutter
with extensions or prolongations pivoted to any suitable part of the apparatus. The
said extensions or prolongations of the shutter are fitted with pins or projections
adapted to work in slots in a suitable plate arranged to slide in ✓ grooves or in any
suitable manner in guides also attached to any convenient part of the apparatus. The
said slots are formed curved so that the extremities of the same are in proximity to
each other in the above mentioned plate and when the said pins are at either extremities
of the said slots the shutter will be in a closed position. The said plate is also
provided with a pin or projection adapted to engage in a slot in the extremity of a
lever attached to a suitable spindle pivoted to any convenient part of the apparatus.
This lever is provided with a spring which acts upon the said lever so as to tend to
keep the latter constantly depressed that is to say in its closed position, and thus to
maintain the hereinbefore mentioned slotted plate normally at one end of its stroke
the pins or projections being at the upper extremities of the slots. The spindle of the
said lever projects through the case of the apparatus, and is provided with a handle by

page_text: means of which the mechanism of the apparatus can be set or cocked as hereinafter
described. The said handle is moreover provided with a pointer adapted to indicate
upon a suitable dial when the said mechanism is set or cocked. To set or cock the
said mechanism I provide a lever pivoted to a bracket attached to the guides carrying
the hereinbefore mentioned slotted plate. The said lever is provided with a suitable
spring and has a shoulder or projection adapted to engage with the herein before
described pin or projection upon the slotted plate, and thus maintain the latter at the
top of its stroke, and the pins or projections at the lower extremities of the said slots.
The said lever is moreover provided with an extension arranged to act in connection
with any well known pneumatic device by means of which the said lever can be
actuated so as to release the hereinbefore mentioned pin or projection upon the slotted
plate from the shoulder or projection upon the said lever, and allow the said slotted
plate to descend to the bottom of its stroke. During the descent of the said
slotted plate the parts of the shutter are opened by the pins upon the extensions of the
said shutter passing round the hereinbefore described curved slots, the shutter being com-
pletely open when the pins are at the greatest distance apart in the said slots. Instead
of employing a pneumatic device to actuate the herein before described lever I some-
times cause the extremity of the said lever or an attachment to any part of the said
lever to extend through the case of the apparatus so that the slotted plate can be
released by operating the same.
In some instances moreover I provide a time limit so that the duration of the
exposure can be regulated to last for any predetermined length of time. To
accomplish this object I provide a suitable train of clockwork mechanism, which
can be wound from the outside of the apparatus by means of a convenient
handle; a pointer being also provided to indicate upon a suitable dial the duration
of the exposure.
1 moreover provide means for starting the said time limit comprising a lever arranged
to be actuated by the slotted slide when the latter is at the beginning of its stroke. The
said lover is thus caused to bear against a spring or pawl and cause the latter to
engage with a toothed ratchet or other wheel and thus allow the time limit to be
employed. Underneath the hereinbefore described lever engaging with the pin or
projection upon the slotted plate, and pivoted to the same bracket attached to the
guides of the latter is another lever, or inside lever provided with a pin or projection
bearing against the first mentioned upper or outside lever and with a suitable spring
adapted to cause the said lever to follow the movement of the said upper or outside
lever. The said lower or inside lever has at its lower extremity a projection or
hook adapted to engage with the herein before mentioned pin or projection upon the
slotted plate and retain the same in such a position that the pins or projections upon
the extensions of the shutter are at the greatest distance apart in the said slots
and therefore the said shutter is in its open position. The said shutter is retained in
this position until the time limit (which has been released by the partial descent of the
slotted plate, releasing the lever and pawl hereinbefore mentioned) unlocks the said
inner lever by a projection upon the said toothed or ratchet wheel, or any suitable
toothed or other wheel of the clockwork mechanism impinging against an extension
of the said inner lever and tilting the same, when the shutter instantly closes. Or
the said shutter can be closed at any time during the operation of the said time limit,
by releasing the upper or outer lever.
I prefer to employ moreover a suitable catch adapted to engage with the herein-
before described pointer and thus lock the said time limit and prevent it from operating
when not required. I can however employ any other convenient means for this
purpose.
When the said time limit is locked, by setting or cocking the hereinbefore
described mechanism, the shutter can be opened and retained in that position
at will by actuating the pneumatic device, or by operating the mechanism
by hand.
I sometimes moreover provide a cam capable of being moved from the outside of
the case of the apparatus and adapted to bear against the hereinbefore mentioned pin

page_text: or projection upon the inner lever and thus actuate both the inner and outer levers.
The shutter is thus opened and will remain in that position until the said cam is again
moved out of gear with the said pin or projection.
The above described shutter can be placed either before or behind the lens or lenses,
or it may in cases where a combination of lenses are employed, be placed between
the said lenses.
Moreover in some instances 1 provide a hood or screen, composed of any suitable
substance, so as to give a greater proportion of light to one part of the sensitive
plate or tissue than to another As for example to give the full amount of exposure
to the foreground, but a less proportion to the sky. To effect the above object I
prefer to place a hood or screen, of such a form or shape in the passage of the light
as to abstract the required proportion of the rays travelling to any part of the said
sensitive plate or tissue. The sky may be thus deprived of any required proportion of
light in a uniform or varying degree. The above described hood or screen, is placed
either in front or behind the lens, and is so arranged as to be capable of adjustment
to any extent required. Either one or more of the said hoods or screens can be
employed.
Although I have herein before described a convenient and advantageous method
of carrying my said invention into practice, it is obvious that I can modify the con-
struction of my apparatus without however in any way departing from the nature
of my said invention. And moreover that a portion of my said invention that
is to say the herein before described mechanism for instantaneously opening and
closing a photographic shutter, the time limit, the means for retaining the said
shutter open at will and the hereinbefore described hood are applicable to drop
shutters, revolving shutters, hinge shutters, or photographic shutters of any other
description.
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: the upper extremities of the slots a, and b, respectively and the edges of the shutters a₁
and will then be in contact with each other and the aperture for the lens will be
closed.
The spindle a projects through the case enclosing the apparatus and is provided
with the handle d₁ by means of which the mechanism of the apparatus can be set
or cocked as hereinafter described.
The spindle d is provided with an indicator d, to show on a dial on the outside
of the case when the mechanism is set or cocked. To set or cock the mechanism'
I provide a lever f pivoted to the front of the front frame plate at f₁ but raised
sufficiently above the frame plate to allow free movement to the lever g hereinafter
described.
The lever is provided with a shoulder at f, and is actuated by a spring f
adapted to keep the lever notch f, normally in a position to engage with the pin or
projection e upon the slotted plate c, and thus maintain the latter at the top of its
stroke. The pins a and b, will then be at the lower ends of the slots and the
parts of the shutter will be closed and ready for action. The lever f has an extension f
acted upon by a pneumatic piston and cylinder f, by forcing air into which the
lever can be actuated so as to release the pin e and allow the slotted plate c to descend
to the bottom of its stroke. During the descent, the parts of the shutter will be
completely opened and then closed again. By raising the projection ƒ the shutter
may be released by hand instead of by using the pneumatic arrangement.
The above described pieces of mechanism are all that are required for instan-
taneous exposures.
For timed exposures I employ a peculiarly shaped lever g
pivoted on the front of the front frame plate at g₁.
Its lower end is provided with a hook g,, hereinbefore mentioned, to engage with
the pine when the shutters are fully open.
At the upper end of this lever g there is fixed a pin 9, projecting immediately to
the left of the upper end of the lever f.
The pin 9, is normally kept in contact with the upper end of the lever f by
means of the spring 9. At 9, the lever is bent at right angles to itself and projects
hackwards through an aperture in the front plate so that it can engage with the
pin h on the wheel h hereinafter described.
Thus when the shutter is set as hereinbefore described and then released by
actuating the lever f, the pin e falls into contact with the hook g, and the shutter
is then kept open until the pneumatic device or the projection f is actuated when
the desired exposure has been given. The lever fis then forced back by the spring f
into its former position, at the same time pressing against the pin 9, and releasing
the hook g2 by overcoming the pressure of the spring 9, which is much weaker than
the spring fs. The pine being thus released, the lever c falls to its lowest position
and the shutter is closed.
h is a toothed wheel fixed on an arbor pivoted at h₁ between the back and front
frame plates and actuated by a spiral spring wound round the arbor behind the
wheel and in such a manner as to cause the wheel to revolve in the direction
indicated by the arrow. The speed at which the wheel h. revolves is governed' by
a fly on the pinion, worked by means of the intermediate wheel and pinion h₂,
the wheel h, being behind the wheel h.
The arbor at h, projects through the outer case and is provided with a handle to
wind the spring. It is also provided with a pointer p fixed to the arbor outside the
case, one use of this pointer is to indicate upon a dial on the case, the amount of ex-
posure to be given & which is regulated by the amount of turning given to the
handle, the dial having been previously graduated. The other use of the pointer p is
to hold the arbor & wheel h when required, in such a position that the pin herein-
after described is out of contact with the lever g at 9.. This is done by allowing the
end of the pointer p to rest against the pawl n. The pawl n is pivoted at n₁ and can
be turned about that point so as to disengage with the pointer p.
On the rim of the wheel his fixed a pin or projection herein before mentioned-
projecting in the direction of the front frame plate. When the wheel h revolves, this

page_text: pin will come into contact with the lever at the point g, and the spiral spring at h
being stronger than the spring g₁, the lever will move round until arrested by the
ping, fixed to the front of the front frame plate. Thus had the shutter been set in
the manner hereinbefore described, then released by the lever f and arrested by the
hook 92, it could remain open until released by the pin h actuating the lever 9 by
means of the point g, and thereby releasing the hook 9, when the shutter would close
as herein before described.
The length of the exposure depending upon the amount that the wheel / is turned
back. In order that the wheel h may be conveniently held back and also that it may
be released simultaneously with the opening of the shutter, I provide a spring & fixed
at one end to the back of the front frame plate, the other end being free but
almost touching the points of the teeth of the wheel at k₁.
In order that the spring k may act as a pawl to the wheel hand thus hold it in
any desired position, I provide a lever pivoted to the back of the front frame
plate at . The lever projects to the point l, where it rests in contact with the
spring k, the lever also projects in an opposite direction, to the point l, preferably
provided with a set-screw. When the shutter is set as hereinbefore described, one
corner c, of the slotted plate c presses against the lever at ls, thereby pressing the
point, against the spring k and depressing the end of the spring k against the
toothed wheel h at k₁. When in this condition the wheel can be set by turning
it back the required amount, and it will then be held as long as the spring presses
against it. When therefore the shutter is set and then released by the pneumatic
device or by hand it opens wide and is held by the hook 9,; at the same time the
wheel h is also released by the pressure being removed from the spring k through the
lever having been released at the point 13. The point h, then travels round until it
comes into contact with the point g, when trips up the lever g releasing tho hook g,
and the shutter closes as hereinbefore described.
For giving exposures by hand at the discretion of the operator, it is necessary to
put the clockwork out of gear with the other apparatus, by turning back the wheel h
so that the pin h is out of contact with the lever g; it is then held back by the pawl n
arresting the pointer pas hereinbefore described. For giving instantaneous exposures
the pin h is allowed to press against the lever g at g, and thus hold back the hook 9,.
Thus when the shutter is set and released, the motion is continuous, there being
nothing to arrest it.
In using the clockwork gear, the pawl n must be turned round so as not to be in a
position to engage with the pointer p. It is then necessary to cock the shutter as
hereinbefore described, then set the time mark to the time required. When roleasing
the lever to make an exposure-keep it released until the shutter is automatically
closed through the clockwork gear, but if it is required to close the shutter sooner
than the clockwork has been set for, it is merely necessary to let the lever f return
to its normal position, when it will cause the shutter to close as herein before described.
If it is desired to keep the shutter permanently open for any length of time, the
shutter is set as before, and the cam m fixed to an arbor pivoted at m₁, and working
upon the front of the front frame plate, is turned in the direction indicated by the
arrow when it will press against the upper end of the lever g at gs, partly rotating
the lever and making the hook 92 project so that it may arrest the pin e and thus keep
the shutter open.
At the same time the pin ga presses against the upper end of the
lever and releases the pin e from the notch fs. The slotted plate c then descends
until arrested by the pin e coming into contact with the hook 9. The shutter is then
fully open and will remain so until the cam m is turned back again so as to release the
lever g, when the shutter will close. The arbor at m₁ projects through the outer case
and is provided with a suitable handle for turning it and also an indicator and
dial to show its position.
Although I have hereinbefore described a convenient and advantageous method of
carrying my said invention into practice, it is obvious that I can modify the construction
of my apparatus without in any way departing from the nature of my said invention,
and moreover that a portion of my said invention, that is to say, the bereinbefore

page_text: described mechanism for instantaneously opening and closing a photographic shutter,
the time limit and the means of retaining the said shutter open at will are applicable
to drop.shutters, revolving shutters, hinge shutters, or photographic shutters of any
other description.
The various parts may be made of sheet metal or other suitable material.
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 spring actuated lever with the notch f, working
in connection with the pin or projection e. Also the extension off working in
connection with the pin or projection 9, substantially as and for the purposes herein-
before described and represented in the drawing annexed.
2. In photographic shutters the spring actuated piece g with parts or projections
92193 and 99, working in connection with the pin or projection e, g, working in
connection with the extension of the lever f, and g, working in connection with the
pin or projection h. substantially as and for the purposes herein before described and
represented in the drawing annexed.
3. In photographic shutters the lever / acted upon by the piece c through the set-
screw, & acting upon the spring k at 1, substantially as and for the purposes
hereinbefore described and represented in the drawing annexed.
4. In photographic shutters the spring actuated wheel h provided with the pin or
projection h working in connection with the point or extension g, and acted upon by
the lever through the spring k. The wheel h also being in connection with the
pointer p working in connection with the pawl a substantially as and for the purposes
hereinbefore described and represented in the drawings annexed.
5. In photographic shutters the spring k acting upon the wheel h and acted upon
by the lever substantially as and for the purposes herein before described and
represented in the drawing annexed.
6 In photographic shutters the piece or lever c-with the pin or projection e acting
in connection with the levers fand g-and the projection or corner c₁ acting against
the lever at 1, substantially as and for the purposes hereinbefore described and
represented in the drawing annexed.
7. In photographic shutters the piece or cam m acting upon the levers g and y
substantially as and for the purposes hereinbefore described and represented in the
drawing annexed.
8. The improved arrangement construction and combination of the several parts of
the mechanism for operating photographic shutters substantially in the manner and
for the several purposes hereinbefore described and represented in the drawings
hereunto annexed.
Dated this 2nd day of February 1889.