Year: 1897

page_text: I, HENRY TATTERSALL, of Birchanger, in the County of Essex, Scientific Instru-
ment Maker, do hereby declare the nature of this invention to be as follows:-
:-
The shutter, which is of the roller blind type consists of a box or case carrying
two rollers, one containing the motive spring. The spindle of the other (the wind-
ing roller is provided with two projecting arms which make contact with two stops
fixed on opposite sides of an oscillating disc, which has a limited rotation on the
releasing lever.
Exposures are made by raising the releasing lever-when adjusted for "time"
exposures (so called) the shutter opens when the lever is raised, & closes on the
lever replacing. The use of the oscillating disc obviates the necessity for any
gearing on the spindle of the winding roller.
1
LT
of T.1007
I, HENRY TATTERSALL, of 3, Park Villas, Birchanger, Bishops Stortford, in the
County of Hertford, Scientific 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 invention relates to an improved photographic shutter suitable both for
instantaneous as well as for time exposure work.
My improved shutter is constructed on the roller blind principle, and consists of
a metal or other box, having an aperture at its centre to take the lens, and provided
with a roller at each end to which the ends of a flexible strip of an opaque material
are secured. This blind is constructed with a central aperture similar to the blind
in common use for this purpose. One of the rollers is provided with a motive
spring, whilst the spindle of the other or winding roller is provided with two
projecting arms which make contact with two stops fixed on opposite sides of an
oscillating disc, which has a limited rotation on the releasing lever.
Means are
provided for winding and releasing the rollers as hereinafter described. Exposures
are made by raising the releasing lever. The apparatus is adjustable either for
"
time
instantaneous
exposures, or for
exposures in the manner hereinafter
"
set forth.
"
"
In order more clearly to explain the action of my device, and the best method

page_text: known to me of carrying the same into effect I will now proceed to describe the
same with reference to the accompanying drawing in which
Figure 1 shews a front elevation of the device.
Figure 2 an end view of the same.
Figure 3 another end view shewing the releasing mechanism.
Figures 4, 5, 6, and 7 shew details of the said releasing mechanism.
The upper blind roller C upon which the blind is coiled when the said apparatus
is set for action, is provided at the back with a pulley and cord C¹ by means of which
it can be actuated. The said roller has its spindle projecting to the outside at the
front end of the case, which spindle carries the two arms I and J. The releasing
lever G carries at its end L an oscillating plate K having a limited motion around
the pin K, and bearing two projecting lugs, one on the. under side marked A, the
other on the upper side marked B (see Figures 3 and 4). These lugs are arranged
to engage respectively with the projections I and J of the spindle C. The lever G
has its upper part L arranged as shewn more particularly in Figure 6, and upon it is
secured the pin K¹ of the plate K whose motion is limited by the engaging of the
projection A in the cut-out portion of the said lever G, which is marked L¹. The
said lever G has moreover a slot E through which passes the stud of the lever D
whereby the mechanism can be set for instantaneous or "time"
explained later on. The roller H is provided with an internal coil spring, the
tension of which is regulated by the knob at the end. The spindle C carries a
roller of such a diameter that two complete revolutions wind up the blind to the full.
F is a spring stop controlling the revolution of the spindle Ĥ. The operation of
the device is as follows:
exposures, as
The blind having been wound up to the full by pulling the cord C₁ on the roller
of the spindle C, the same is held in position against the tension of the spring by
the lug A on the oscillating piece K coming in contact with the inner projecting
lug J of the spindle C. If, however, the lever G be raised by means of the
pneumatic device or otherwise the said arm J is released from A, and the blind
rewinds on the spring roller H, thus making the exposure.
"
For this operation the lever D must be adjusted to the part of the slot E for
instantaneous exposures. If, however, the lever D be shifted into the position
for "time" exposures, that is to say, towards the spindle H the lever G is moved
inwards closer to the spindle C, and the outer lug B on K comes within reach of
the outer lug I on the spindle C. Consequently when the mechanism is released
the said lug I, on the spindle completing one revolution, will strike against the
lug B on the upper side of the oscillating plate K, thus preventing the blind from
unwinding to the full, and leaving the aperture in the blind, and the shutter
respectively coincident.
The exposure will thus continue as long as may be desired until the lever G is
again pressed out, when the arm I being released, the revolution of the spindle C
is completed, and the shutter is closed. The lever G may be actuated by means of
a pneumatic tube or otherwise; a speed indicator may be affixed on the end of the
spindle H.
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 a photographic roller blind shutter mechanism the application of an
oscillating plate having a limited rotation, pivoted on the releasing lever, and
provided with an inwardly and outwardly projecting lug respectively, substantially
as described.
2. In a photographic roller blind shutter mechanism the combination of the
oscillating plate K provided with the lugs A and B pivoted upon the end L of the
lever G with a roller capable of making two complete revolutions affixed on a
spindle carrying the two projecting arms I and J substantially as, and for the
purposes described.

page_text: 3. The combination of parts forming the improved photographic roller blind
shutter, substantially as described with reference to the accompanying drawings.
Dated this 15th day of March 1898.
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicant.