Improvements in Apparatus for Projecting Kinetoscope Pictures on the Screen.
Year: 1896

page_text: Date of Application, 2nd Mar, 1890
Complete Specification Left, 30th Nov., 1896-Accepted, 23rd Jan., 1897
спа
7090
Complete Specification Left, 30th Nov., 1896-Accepted, 23rd Jan., 1897
PROVISIONAL SPECIFICATION.
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Projecting Kinetoscope Pictures on
the Screen.
I, ROBERT WILLIAM PAUL, of 44 Hatton Garden, and 114-15 Great
Saffron Hill, London, E.C., Electrician and Scientific Instrument Maker, do
hereby declare the nature of this invention to be as follows:-
My invention relates to an improved apparatus for producing representations of
moving scenes, figures or objects by projecting onto a screen in rapid succession by
means of an optical or "magic" lantern or other suitable projecting apparatus, a
series of photographic pictures of such scenes, figures or objects taken in rapid
succession so as to represent the various changes in the appearance of such scenes,
figures or objects. And my said invention comprises improvements in the
mechanism for propelling the film containing the instantaneous photographs,
which produce this effect. In order to give a definite position to the picture on
the film which is to be projected I prefer to employ the following mechanism,
consisting of two sprocket wheels gearing into holes in the film, and placed a few
inches apart and geared together by suitable mechanism which gives thus an
intermittent motion of rotation, causing the film to be propelled instantaneously a
small amount, after which it remains still for projection of the picture. The
portion of the film which is projected is that between the two sprocket wheels,
which is thus kept taut and free from slack, so as to avoid any irregularity or
indefiniteness in the position of the picture.
Dated this Second der of March 1806
Improvements in Apparatus for Projecting Kinetoscope Pictures on
the Screen.
I, ROBERT WILLIAM PAUL, of 44 Hatton Garden and 114-15 Great
Saffron Hill, London, E.C., Electrician and 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 apparatus for producing representations of
moving scenes, figures or objects by projecting onto a screen in rapid succession,
by means of an optical or "magic" lantern or other suitable projecting apparatus,
a series of photographic pictures of such scenes, figures or objects taken in rapid
succession so as to represent the various changes in the appearance of such scenes,
figures or objects.
In some of the forms of apparatus heretofore devised for this purpose, a band
or film has been employed which is intermittently fed over rollers through the

page_text: optical system of a projecting lantern, the light being shut off by an inter-
mittently moving shutter whilst the film is in motion. The means employed for
effecting these motions have, however, been imperfect in the following particulars,
viz. they have not held the film perfectly flat and taut and in a fixed position
during exposure by positively controlling its motion both in advance of and in
rear of the opening or window through which the light shines to project the
picture; consequently the pictures successively projected do not accurately
register with one another and they do not lie exactly in the same plane while
being projected, and further the film is liable to curl or assume a curved form,
with the result. that the effect obtained on the screen is blurred and unsteady.
Now the main object of my present invention is to ensure that each picture,
while being projected, shall be kept perfectly flat and taut and be rigidly held in
accurate register with the preceding picture or pictures and in exactly the plane
which the latter previously occupied. For this purpose I employ two driving
wheels or drums for feeding forward the film or band bearing the photographic
pictures, one of which wheels or drums is arranged immediately in advance and
the other immediately in rear of that part of the film through which the light
shines, and which wheels or druns are adapted to be rotated simultaneously about
their axes by means of suitable intermittent gearing so constructed as to hold the
said driving wheels or drums rigidly and correctly in position whilst the pictures
are being projected.
To more effectually ensure the keeping of the said film or hand in a definite
position relatively to the optical system of the apparatus, and prevent slackness
of the said film or band between the said driving wheels or drums and the spools
for supplying and receiving such film or band, I prefer that the said film or
band should be continuously pressed against a frame around the aperture or
window through which the pictures are projected, by means of a series of spring.
pressed pads, which, whilst holding it against the said frame, permit of its sliding
freely past the same as required. I also prefer that slackness of the film
between the second driving drum and the receiving spool or roller should be
prevented by a continuous rolling-up tension exerted on the said spool by means
of a loose or slipping band which exerts a continuous turning moment on the said
spool. The motion of the spool from which the film is unwound should also be
controlled, in this case, by means of a brake-pad pressing thereon. The tension
on the film will then remain approximately constant whatever may be its position
relatively to the spools.
In the accompanying drawings I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure is an elevation, partly in vertical section, showing one side of my
improved apparatus, the parts being illustrated in the positions which they occupy
when the film has been moved through one-half of the distance requisite to effect a
change of the picture.
Figure 2 is an elevation, showing the opposite side of the said apparatus.
Figure 3 is a diagram showing some of the parts in the positions which they
occupy when the film is at rest and a picture is being projected onto the screen.
Figures 4 and 5 are views illustrating details of construction, and
Figure 6 is a side elevation illustrating a slight modification of my invention.
Like letters indicate corresponding parts throughout the drawings.
A is the base of the apparatus and the frame thereof. In the part 1 of the
said frame is provided an aperture or window a through which the light shines,
and in front of which the film or band of pictures is intermittently fed as
bereinafter described.
The film is provided with perforations along its edges as at 1, and, before
use, is preferably wound on a spool or roller D, and is suitably supported in the
frame B. From the spool D, the film C passes over a driving roller or sprocket-
wheel E the pins or teeth of which engage in the perforations & of the film.
After passing in front of, the window a, the film is conducted over a second

page_text: driving roller or sprocket-wheel F the pins or teeth c of which engage in like
manner with the film. The wheels E, F are mounted on arbors E, F, which
turn in suitable bearings in the frame B, and which are provided at their outer
ends with specially formed gear-wheels d, e; the teeth of these wheels dare
curved at the ends to correspond to the curvature of a disc G mounted on the
main driving-shaft J of the apparatus, to which continuous rotary motion is
imparted through a pulley Jor in any other suitable manner. The disc G is
provided with teeth or projections g which are adapted to simultaneously engage
in notches in the gear-wheels d and e respectively, as shown in Figure 2, and
thereby turn the wheels E, F, through an angle corresponding to the pitch of the
consecutive pictures on the film C. When this motion is completed the wheels E, F
are immediately locked in position by the engagement of the periphery of the
dise G with the curved surfaces at the ends of the teeth of the gear-wincels d
and e, as shown in Figure, and thus the immovability of the film C, during the
projection of each picture, is ensured.
After leaving the feed-wheel F, the film is wound onto another spool H,
which is continuously driven from a pulley p on the main driving-shaft J by
means of a loose or slipping band p'. Or the spool I may be dispensed with and
the film C allowed to descend into a basket or other convenient receptacle.
In order to retain the film C in contact with a sufficiently large portion of the
circumference of each of the wheels E, F to enable the said filin to he fed along
without undue pressure on the walls of its perforations b, I provide guide-
rollers h, i, provided with suitable grooves to clear the pins or projections c, and
mounted on pivoted frames k, 1. These frames k, I are acted upon by springs k',
so that the guide-rollers h, i can be either pressed against the film C, on the
wheels E, F, as shown in Figure 1, or held away therefrom to facilitate the
insertion or removal of a film into or from the apparatus.
The motion of the spool D is controlled by means of a brake-pad m mounted on
a spring m (Figures 2 and 5) and pressed against the side of the said spool by
means of an adjusting screw n. By this means, any over-running of the spool and
consequent slackness of the film, when the said spool is set in motion by the said
film, is entirely prevented, the tenson of the said film being regulated, as desired,
by means of the adjusting screw n. A guide covered with velvet. or other soft
material is also provided to receive the film whilst being adjusted in the apparatus
and prevent its coming into contact with parts thereof liable to injure it.
?
The part of the film C passing before the window a is maintained in a constant
position relatively to the optical system of the apparatus, by its being kept taut by
the two sprocket-wheels E, F, and also by means of springs provided at their
ends with presser-pads r, which bear against the borders or edges of the film Con
either side of the picture and press it against a frame s arranged around the
window a.
The pads can be withdrawn from the film C, by means of the cam-
lever K, which, when turned about its axis, causes the springs to be pressed
outwards by the cams K, Figure 4; the film can then be readily removed from the
apparatus and another film substituted therefor.
The optical system preferably consists of a condenser M and objective N which
may be of any suitable construction, the light passing in the direction of the arrow
in Figure 1 froin a suitably arranged source, such as an electric arc-light, an
incandescent cylinder of lime, etc.
The light is cut-off during the motion of the film either by means of a flat disc
shutter having two apertures or slots or by means of a rotating shutter P' com-
prising two curved plates or segments of a cylinder P, and preferably arranged
between the window a and the condenser M; it may, however, be arranged in any
other suitable position. The segments P1 shut off the light as shown in Figure 1,
while the film is being moved, but allow the light to pass between them as shown
in Figure 3, while the film is at rest. This shutter is mounted in suitable bearings
in the frame B and is continuously rotated through spur-genring t, t, Figure 2,
from the main-driving-shaft J. A perforated slide R, Figure 1, capable of being

page_text: fixed in any desired position by means of adjusting-screws R', is provided for
varying the position of the window or aperture a, as required.
I also provide means whereby the inclination of the apparatus may be varied so
as to obtain the best effects on any given screen. For this purpose the base A of
the apparatus is provided with a cup-shaped sent u, Figure 1. resting on a hemi-
spherical surface u' and is secured at any desired inclination relatively to the
supporting table by means of bolts provided with wing-nuts and passing
through holes or slots in the base A and table Q.
In using the apparatus, the film C is inserted into the same so that the pictures
register with the window a, and the main driving-shaft is turned in the direction
indicated by the arrow in Figure 2, by means of an electro-motor or by hand
or by other convenient means whereby an equal turning moment miny be
obtained; the pictures will then be projected onto the screen in rapid succession,
the window a being closed by the shutter F during each movement of the film and
being open while the film is stationary, and the rate at which the film is fed being
arranged so as to produce the best effect.
Instead of connecting the upper sprocket-wheel E directly to its axis, I sometimes
mount it loosely on its axis not connect it therewith by a spring tending to press
the wheel against a stop on its axis hut which will yield under a predetermined
pressure, so that the said sprocket-wheel is capable of a small angular movement
independently of the sprocket-wheel F to compensate for variations in the pitch of
the holes in the different films or bands, thus obviating any liability to either
over-stretching or undue slackness of the film between the two sprocket-wheels E
and F. The apparatus constructed as above described I sometimes use as a camera
for producing the photographic pictures on the films or bands, in which case
I prefer to use a shutter of disc-form instead of the shutter shown in the drawings.
To more effectually ensure the accurate operation of the apparatus, I sometimes
employ, in conjunction with the two sprocket-wheels above described, another
sprocket-wheel W, Figure 6, which also engages with the film or band C and
which is arranged to be driven continuously from the driving-shaft at a lower
speed than the sprocket-wheels E, F, which are, as above described, rotated
intermittently. This auxiliary sprocket-wheel W serves to continue the drawing
of the film from the spool while the wheels E, F are at rest, so that, when the
latter again begin to rotate, a portion of the film or band of sufficient length will
be free to be fed forward by the same. In combination with the wheol W
1 provide a presser roller mounted on a pivoted army acted upon by a
spring y'.
In some instances, I also provide another auxiliary sprocket-wheel Y similarly
arranged between the sprocket-wheel F and the spool H. By these means I make
the apparatus reversible, so that, after the film has been unwound from the spool D
and wound upon the spool H, its motion can then be reversed so as to exhibit the
pictures successively in inverse order. The mechanism can in this case be rotated
alternately in either direction either by hand or by a suitable electric or other
motor.
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
First. An apparatus for the purposes above specified, comprising intermittently-
rotating sprocket-wheels engaging with the film or band both in advance and in
rear of the opening through which the light shines, for the purpose specified.
Second. The combination, with the intermittently-rotating sprocket-wheels,
engaging with the film or band both in advance and in rear of the light-opening,
of a frame surrounding the said light-opening, presser-pads for pressing the film or
band against the said frame, and means for temporarily withdrawing the said pads
from the film or band, substantially as hereinbefore described and for the purposes
specified.

page_text: Third. The combination, with the intermittently-rotating sprocket-wheels
engaging with the film or band both in advance and in rear of the light-opening, of
a spool for receiving the film after use, arranged substantially as hereinbefore
described so as to continuously exert a suitable tension on the said film, for the
purpose specified.
Fourth. The modification of my invention in which the intermittently-rotating
sprocket-wheel in rear of the light-opening is mounted so that it is capable of
turning about its axis through a small angle, and is held against a stop on its axis
by a spring, as, and for the purposes, above specified.
Fifth. The combination, with the intermittently-rotating sprocket-wheels
engaging with the film or band both in advance and in rear of the light-opening,
of an auxiliary continuously-rotating sprocket-wheel also engaging with the film or
band, substantially as, and for the purposes, above specified.
Sixth. An apparatus for the purposes above specified, provided with intermittently-
rotating sprocket-wheels engaging with the 6lm or band both in advance and in
rear of the light-opening, which apparatus is so constructed that the film or band
can be fed through the same alternately in either direction, substantially as
described.
Seventh. The improved apparatus constructed substantially as described with
reference to the accompanying drawings and operating as, and for the purposes,
above specified.
ROBT. W. PAUL.
D. Young & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.
ROBT. W. PAUL.
D. Young & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.