Improvements in Apparatus for Animated Photography and Optical Projection.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Animated Photography and Optical
Projection.
I, JOHN ALFRED PRESTWICH, of 744, High Road, Tottenham, in the County of
Middlesex, Engineer, do hereby declare the nature of this invention to be as
follows;-
This invention has reference to improvements in apparatus for taking, printing
and projecting, kinetoscopic pictures.
The improvements consist chiefly in the mechanism for imparting to the photo-
graphic film the necessary rapid intermittent movement. In carrying out my
invention I employ mechanical motions made on the following principle. When
the film is small and thus the traverse of the film for each successive picture is
small, a disc is mounted on the end of a spindle about which it revolves. On this
disc is mounted another spindle forming a kind of long crank pin which has its
centre a distance from the centre of the dise about equal to one half the distance
it is required to pull the film each period, the throw of this spindle or crank pin
will therefor be equal to the pull of the film required.
On this spindle is mounted a light rectangular frame of suitable construction,
one end of which is jointed to a link, the other end of the link being jointed to a
pin fastened to the bed plate or other part of the apparatus. To the sides of this
end of the frame are also fastened two flat springs, which carry at the other end,
pins which engage in the holes in the edges of the film. These springs press on
a plate which forms one side of the film race, the pins passing through slots in
the plate, and engage the holes in the film.
In their normal condition the free ends of the springs stand away from the
frame and the amount of play is checked by suitable means connected to the other
end of frame. The engagement of the pins with the film may be effected in any
other convenient method.
The action is as follows:-On the forward and downward stroke of the crank
pin, the springs come in contact with the plate above mentioned, the pins engaging
in the holes of the film. On the further travel of the crank, pin and frame, the
springs are sprung back till the crank reaches the quarter centre or half its down
travel, when the springs begin to come back to their normal position, and the
downward movement of the frame and film, continues till the crank reaches its
bottom position, when the checks draw the free ends of the springs and the pins
from the plate. During the upward movement of the frame, the film remains at
rest, until the crank pin again reaches the top of its stroke.
16-1
1000
J. C. MEWBURN & ELLIS,
65 and 50, Chancery Lane, London, Chartered Patent Agents.

page_text: Improvements in Apparatus for Animated Photography and Optical
Projection.
I, ALFRED JOHN PRESTWICH, of 744, High Road, Tottenham, in the County of
Middlesex, Engineer, 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 has reference, to apparatus for taking, printing and projecting
kinetoscopic pictures, and its object is to provide novel film-actuating mechanism
for use in such apparatus and to impart to the photographic film the necessary
rapid intermittent movement by essentially simple and efficient means.
In carrying out my invention I employ mechanical motions constructed to
operate on the principle hereinafter described..
My invention will be fully understood from the following description and the
annexed drawings, in which latter Figure 1 is a side elevation and Figure 2 a rear
end elevation of film-actuating mechanism constructed in accordance with the
improvements, the construction shown being suitable when the film is small and
thus the traverse of the film for each successive picture is small.
Referring to the drawings, a is a disc mounted on the end of a spindle b about
which it revolves continuously. On this disc a is mounted another spindle c form-
ing a kind of long crank pin which has its centre a distance from the centre of
the disc about equal to one-half the distance it is required to pull the film each
period; the throw of this spindle or crank pin will therefore be equal to the pull
of the film required.
On this spindle c is rotatably mounted a light frame d d of suitable construction,
the lower end of which is jointed to a link e. The other end of the link o is
jointed to a pin f fastened to the bed-plate g or other fixed part of the apparatus.
To the sides of this end of the frame d d are also fastened two flat springs h h
which carry near their upper free ends pins which engage in the holes in the
edges of the film 7. These springs h h press on a plate m which forms one side of
the film race, the pins i passing through slots n in the plate m and engaging the
holes in the film. Beyond the pins the free ends of the flat springs are bent
back horizontally for a certain distance and then bent downwards vertically at p
in such a manner that the said downwardly bent ends p p will be struck by the
upper ends of the frame parts d d in the upward rotation of the frame.
In their normal condition the free ends of the springs tend to stand away from
the frame d d and the amount of play is thus checked by the bent ends p p coming
in contact with q 9 or by some other suitable means. The engagement of the
pins with the film 7 may be effected in any other convenient method.
:
The action is as follows:-At the highest point of the stroke of the crank pin c
(as indicated by the arrow in Figure 1) the springs h h come in contact with
the plate m above mentioned, the pins i engaging in the holes k
of the film. On the further travel of the crank pin cand frame d d the
springs are sprung back till the crank e reaches the quarter-centre or half its
down travel, when the springs hh begin to come back to their normal position
and the downward movement of the frame d d and film continues till the crank
reaches its bottom position, when the upper ends qq of the frame d d strike against
the ends of the springs and draw the free ends of the springs and the pins
from the plate m. During the upward movement of the frame d d, the film
remains at rest until the crank pin again reaches the highest point of its stroke.
If desired, the crank è may be connected at the lower end of the frame d d and

page_text: the link e be connected in the place of the crank pin. In this case the crank would
turn in the opposite direction to that indicated by the arrow in Figure 1. Instead
of using a link, a slot or a slide can be substituted to control the path of the enḍ
of the frame, as will be readily understood.
It will thus be understood that my invention is susceptible of modification in
its details, it being based upon the employment of flat springs carrying the film-
operating pins, said springs being arranged to yield on coming in contact with
a plate or plates (suitably situated with reference to the film) during the movement
of the film whilst the springs, and consequently the film-operating pins, are moved
back away from the plate and the film by means of suitable rotary or reciprocating
or alternate motion mechanism when the film is required to be stationary.
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:-
-
1. In kinetoscopic film-actuating apparatus, the combination of flat springs
carrying pins with means for alternately engaging said pins with and disengaging
them from the film, substantially as and for the purpose set forth.
2. In kinetoscopic film-actuating apparatus, the combination with flat springs
provided with pins, of mechanism for giving said springs and pins a rotative
motion, and of straight guides against which the springs press, whereby the travel
of said pins while in engagement with the film is rectilinear.
3. In kinetoscopic film-actuating apparatus, the combination of flat springs,
film-engaging pins carried thereby a frame carrying said springs, one end of each
spring being free, a crank dise, a crank pin carried thereby, said frame being
mounted on said crank pin and following its path of rotation, and means controll-
ing the movement of the end of said frame, whereby during a part of the revolution
of said crank pin the frame and springs approach the film and the pins engage the
film and draw it to the required extent, while during further revolution of the
crank pin the frame engages the free ends of the springs and withdraws them
together with their pins from the film, substantially as described.
4. In kinetoscopic film-actuating apparatus, the combination of flat springs,
film-engaging pins carried thereby a frame carrying said springs, one end of each
spring being free, a crank disc, a crank pin carried thereby, said frame being
mounted on said crank pin and following its path of rotation, and a link controll-
ing the movement of the end of said frame, whereby during a portion of the
revolution of said crank pin the frame and springs approach the film and the pins
engage the film and draw it to the required extent, while during further revolution
of the crank pin the frame engages the free ends of the springs and withdraws
them, together with their pins, from the film, substantially as described.
5. Kinetoscopic film-actuating apparatus constructed and operating substantially
as and for the purpose hereinbefore described and represented in the accompanying
drawings.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.