Improvements in Apparatus for Taking, Viewing and Projecting Photographs of Moving Objects.
Year: 1897

page_text: Date of Application, 28th Apr., 1897-Accepted, 23rd Apr.,
1898
COMPLETE SPECIFICATION.
Improvements in Apparatus for Taking, Viewing and Projecting
Photographs of Moving Objects.
I, BIRT ACRES, of Wrotham Cottage, Hadley, Herts, Photographer, do hereby
declare the nature of this invention. and in what manner the same is to be per-
formed, to be partieularly described and ascertained in and by the following
statement:
In taking, viewing and projecting photographs of moving objects the film for
receiving or projecting the images, the successive movements of which with minute
intervals of rest have to be performed very rapidly, I employ two lenses fixed at
a suitable distance apart and I cause the film to be alternately moved and retained
behind each lens, allowing bulges of the film to be formed between and beyond the
lenses, the pictures following each other on the film not in the order of the natural
numbers 1, 2, 3 &c. but in the order 1, 3, 2, 5, 4, 7 &c. and for the purpose of giving
the required movements to the film I arrange apparatus as I shall describe referring
to the accompanying drawings.
Fig. 1 is a vertical section of the photographing apparatus. Figs. 2 and 3 are
sectional plans on the lines 2-2 and 3-3 of Fig. 1 respectively. Fig. 4 is a
plan of the apparatus modified for projecting the pictures.
The film is drawn off the spool J and delivered to the spool K which is driven
by a friction band in the usual way.
The film itself, is moved, as described in my prior Specification No. 10474 of
1895 by a pair of pegged rollers H, H' and also by a pair A A¹ which have on their
spindles ratchet wheels E driven by pawls carried on pinions D driven by recipro-
cating racks projecting to each hand from a slide C which is worked by a connect-
ing rod from a crank F on the main shaft G. The ratchet wheels are also engaged
in the usual way by stationary pawls which prevent them from moving backwards.
Thus at each revolution of the shaft G the slide C makes a to and fro movement
moving the roller A by its stroke to the left while A' remains at rest, then moving
A' by its stroke to the right while A remains at rest.
The shutter L is caused to revolve by chain gear from the shaft G, its aperture
being brought alternately opposite the apertures M through which the film receives
light, at the time when the part of the film facing each aperture is stationary.
The film passes over guide rollers a and a¹ so that when the roller A is revolving,
A being at rest the film is made to form a bulge B¹ between the rollers A and a¹,
and when A is at rest, A¹ in revolving takes up the bulge B₁, a bulge B being
formed between H and a, ready to be taken up when A next revolves. As H¹ is
continuously moving another bulge 132 is formed when A¹ gives off film. Thus,
while the film is continuously fed, bulges are formed while parts of it are at rest,
and these bulges readily give off film to the rollers when they move.
When instead of pegged rollers such as A, A', other appliances such as reciprocat-
ing claws are employed in the known manner for moving the film, I time these
appliances so that the one part of the film is moving while the other part is at
rest, bulges being formed in the same manner as when the pegged rollers are used.

page_text: As shewn in Figure 4, I separate the spools J and K sufficiently to give room
between them for two lenses Ñ N¹ arranged in front of the film which is moved
in the same manner as that already described. Behind the lens N¹ a mirror P¹
is fixed at an angle of 45° to the focal line of N1, and behind the lens N revolves
a mirror P such as is shewn in front view by Figure 5, being a circular disc having
two quadrants open its plane being also at an angle of 45° to the focal line of N.
Parallel rays from a lens Q in a line at right angles to the focal lines of N and N
are during one part of the revolution of the mirror P reflected through N, and
during another part they pass through the openings of P and are reflected by P¹
through N. It is to be understood that the mirror P is so timed in its movement,
that the light passes through N and N¹ at the time when the film is at rest behind
these lenses respectively.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1. Apparatus for taking or viewing photographs of moving objects arranged and
and 3.
operating substantially as described with reference to Figures 1,
2. Apparatus for projecting photographs of moving objects arranged and operat-
ing substantially as described with reference to Figures 4 and 5.
o
ABEL & IMRAY,
Agents for the Applicant.
HOOT YO
Lo S
ΚΟΛΟΣ
ABEL & IMRAY,
Agents for the Applicant.