An Improved Photographic Shutter.
Year: 1898

page_text: ROYAL DITIVATION.
An Improved Photographic Shutter.
We, PERCY WALLIS, of Queensberry Road, Kettering, in the County of
Northampton, Manager, and EUSTACE FREDERIC WALLIS, of the same place,
Solicitor, do hereby declare the nature of this invention to be as follows:-
The shutter is of the roller-blind type but the peculiarity is that the blind is
a continuous band of a light tight material running over two rollers. Two
apertures are pierced in the blind & when the rollers revolve by means of a
spring in one of them these apertures pass across each other thus giving the
necessary exposure.
The two sides of the band are made to run close to one another by means of
two small guiding rollers. The blind rollers are so large that a single turn
or a turn and a half is sufficient to move the blind the necessary amount.
The exposures can be either instantaneous or time by means of a system
of catches attached to one of the rollers & the longer automatic exposures are
given by means of a lever worked by the time catch & which does not allow
the roller to revolve until it has displaced the air contained in a small pneumatic
ball.
Dated this 21st day of September 1898.
PERCY WALLIS.
EUSTACE F. WALLIS.
We, PERCY WALLIS, Manager, and EUSTACE FREDERIC WALLIS, Solicitor, both
of Queensberry Road, Kettering, in the County of Northampton, 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 photographic shutters of the roller blind type, and
is designed to obtain a very much quicker traverse of the blinds across the lens
or a quicker closing of the shutter after being opened than would be possible with
a blind closing or traversing in one direction only.
By this invention we obtain a blind traversing in two directions across the
lens which greatly increases the rapidity of exposure.
It consists essentially in constructing the blind of a continuous band of light

page_text: tight material running over two rollers to which ends or tabs on the blinds are
securely attached, with two apertures one of which passes across the other
as the blinds are drawn from one roller to the other consequent upon the move-
ment of the rollers and in mechanism for drawing up and releasing the blinds.
It will be fully described with reference to the accompanying drawings:-
Fig. 1, is a front elevation of the shutter with the casing removed.
Fig. 2. End elevation showing releasing mechanism in position for
taneous exposure.
32
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"instan-
Fig. 3. End elevation of releasing mechanism when in position for "time"
exposure.
Fig. 4. Transverse section showing position of the roller blind when the shutter
is closed (after exposure).
Fig. 5. Transverse section showing position of the roller blind when the
shutter is open (during exposure).
Fig. 6. Transverse section showing position of the roller blind when the shutter
is closed (before exposure).
Fig. 7. Transverse section showing position of blind before applying to the
rollers.
Fig. 8. Transverse section showing shape of blind when extended.
Fig. 9. Front elevation of blind extended before being attached to the rollers.
The frame or box A and the rollers B and C are of any ordinary shape or
construction employed for roller blinds of photographic shutters.
The blind D is made of three parts or portions, a central portion & which is in
the form of an endless or continuous loop and two end portious and ".
The central or endless part of the blind is formed with two apertures E and E¹
the end part d' is attached to the winding on roller B and the other end part
to the spring roller C.
The blind before being secured to the rollers is turned with the end por-
tions dd inside loop or endless part d (as shown in Fig. 7). The rollers Band (
are also placed inside the loop d and the ends d' d" secured to them by a suitable
wedge or otherwise.
The two sides of the looped portion d of the blind D which are at the opposite
sides of the rollers are made to travel close to each other by curved guide F
inserted in the frame or box A and when in motion the aperture E is travelling
in one direction while the aperture El is travelling in the reverse direction.
The spring roller C is held in tension by the pawl G in the usual way and it
is rotated to increase the tension of the spring by a graduated tape H wound
around one end. The winding on roller is rotated to wind the blind upon it by
the cord K wound around one end of it.
The blind D is held wound upon the roller B against the pull of the spring
roller C by a catch L on the end of the roller spindle 6 placed outside of the box
or frame A which catch L engages with the end m of the spring lever M. The
spring lever M is moved out of the path of the catch L by a pneumatic bulb P
at the end of a tube p to release the blind D. To the lever M is pivoted a
second lever N which when in the same plane as M (as shown in Fig. 3) stops
the catch L when the blind has travelled half its distance and reached the position
shown in Fig. 5, with both apertures d' d" opposite one another exposing the lens
of the camera until the bulb P is deflated when the levers M N spring back to
the position shown in Fig. 1 thus giving what is known as a
66 time exposure.
For an instantaneous exposure without stoppage of the blind in its travel
the second lever N is moved out of the path of travel of the catch L into the
position shown in Fig. 3.
In operation as the blind D travels either when being wound onto the roller B
or from the roller B to the spring roller C the apertures E E therein move
simultaneously in opposite directions thus uncovering and again covering the
lens in half the time that is the case where a blind with a single aperture is
employed in the ordinary way.

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is: -
1. A roller blind for photographic shutters constructed with a central looped
portion which passes round the rollers provided with two apertures which travel
in opposite directions and end portions on tabs by which the blind is attached
to the rollers substantially as described.
2. In a photographic shutter for time and instantaneous exposure the
releasing mechanism comprising the catch L on the end of the roller the lever M
moved by the pneumatic bulb P and the second lever N pivoted thereto which can
be moved into or out of the path of the catch L substantially as described.
3. A photographic shutter having the several parts constructed and arranged
in combination substantially as described and shown.
Dated this 7th day of March 1899.
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.