An Improved Automatic Slide Carrier for Optical Lanterns.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
An Improved Automatic Slide Carrier for Optical Lanterns.
1, LEWIS ERNEST HOPKINS, of 189, Castle Road, Cardiff, in the County of
Glamorgan, Accountant, do hereby declare the nature of this invention
to be as follows:
The object of this invention is to provide an optical lantern, with a better method
of automatically changing the slides than those hitherto known.
My invention consists of a carrier placed in front of the condenser, and held in
position in the usual way.
The slides are dropped in vertically at one side of the carrier which is extended
upwards to about double the length of the slide.
The length of the carrier is such as to take exactly three slides of three and a
quarter inches each-the length of the said slides occupying the entire working
length of the carrier.
When the three slides are in the carrier, the centre one is in position for being
exhibited.
Openings will be cut as usual in the centre of the carrier to allow the light to
pass through.
Upon the inlet side of the carrier is placed a bar, actuated by a spring. This
bar forces forward the slides and keeps them well up against the outlet end of the
carrier. The outlet taking place vertically so that upon withdrawing the slide at
that end of the carrier the said bar with the spring arrangement forces the two
remaining slides onward automatically when a new slide is pressed downwards
against the side of the bar. This slide occupying the empty space below, vacated
by the before mentioned action of the bar, so that whenever a slide is withdrawn.
from the outlet end of the carrier a fresh one automatically takes the place of
The sides of the carrier at each end are cut
the one previously in the centre.
away at the top part so as to allow the fingers of the operator to insert and take
away, the slides.
The bar is bent to a certain angle, to permit of the entering slide, pressing it
backwards against the spring: the end of the bar projecting forward, to follow
up the slide in order to ensure of the one on exhibition being correctly in its
place.
The bottom of the carrier, whereon the slides rest, is preferably made V-shaped
so that thin slides might always be kept central. This V-groove might be made
of metal or other hard substance.
The sides and body of the carrier are preferably made of wood, but I sometimes
employ metal or other suitable substance.
At the exit. end of the carrier an elastic cushion of any suitable material, may
be applied, so that the slides are forced up noiselessly into position.

page_text: The metal is carried slightly above the entering side of the carrier, so that it
may be pressed by the finger and worked by hand if necessary.
In this specification I have hitherto described a carrier for taking three slides
only, but in some cases it is more convenient to have a carrier, of greater length,
in which case the currier may be made to contain four or more slides otherwise,
the details in both cases are the same.
When a new slide is being inserted, into the carrier and has pressed back the
bar 1 place in the bottom of the carrier a small spring which engages with the bar,
and prevents it from pressing on the slide so that the new slide, or the one that is
being last inserted shall drop down easily to the bottom without rubbing against
the slide that is being exhibited.
The pressing down of the incoming slide when it arrives at the bottom of the
carrier, depresses the spring and frees the metal bar which then follows the slide in a
horizontal direction, squeezing it home against the other slides.
An Improved Automatic Slide Carrier for Optical Lanterns.
I, LEWIS ERNEST HOPKINS, of 189, Castle Road, Cardiff, in the County of
Glamorgan, Accountant, 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:-
The object of this invention is to provide an optical lantern with a better method
of automatically changing the slides than I am hitherto acquainted with.
My invention consists of a carrier placed in front of the condenser, and kept
in place in the usual way, it not being essential that the lantern be what is known
as open fronted.
In the drawings,
Fig. 1 is an elevation of my improved carrier.
Fig. 2 is a section through the carrier on the dotted line in Fig. 1.
Fig. 3 is a similar view to Fig. 1, but with one of the side plates removed to
expose the interior mechanism, and showing the slides in position.
Fig. 4 is a plan of Fig. 1.
Fig. 5 is a similar view to Fig. 8. but showing the mechanism in the net of
changing the slide on exhibition.
Fig. 6 is a similar view to Fig. 5, but showing the new slide in position for
exhibition and the next slide being inserted.
Like numbers indicate corresponding parts in all the figures.
Referring to the drawings.
provide a hollow casing preferably of wood though I can use metal or other
suitable material, consisting of two sides 1, 1, kept apart by ribs or distance
pieces, 2,2,2 of such thickness as to permit of ordinary slides passing easily
between the sides.1, 1. The length of the casing is such as to take three slides
of the size commonly in use.
The slides are dropped in vertically at one end of the carrier, which is, at that
end, extended upwards to about double the length of the slide.
When three slides are in the carrier, the centre one is in position for being
exhibited.

page_text: Openings, 3, are cut as usual in the sides of the carrier, to allow the light to
pass through. Upon the inlet side of the carrier, and between the side plates
thereof, a metal bar 4, actuated by a spring 5, is pivoted at its upper end 6.
This bar forces forward the three slides, and keeps them well up against the
stop at the outlet end of the carrier.
The outlet takes place vertically, so that, upon withdrawing the slide at that end
of the carrier, the metal bar 4, actuated by the spring 5, forces the two remaining
slides onward automatically, as shown in Fig. 5, until they reach the stop 7, as
shown in Fig. 6.
The next slide for exhibition is now pressed down in the two grooves formed by
the upward projections S, 9, of the sides of the casing, and in so doing, the bar 1
is pressed back against, and compresses, the spring 5, into the position shown in
Fig. 6. On reaching the bottom of the casing, the bar 4 forces this slide against
the remaining two, and the apparatus is again ready for operating, so that upon
removing a slide from the outlet end by lifting it vertically over the stop 7, a fresh
slide automatically and instantly takes the place of the one previously in the
centre.
It will also be seen that it is impossible to allow the space opposite the open-
ings 3, to become vacant at any time during an exhibition thus obviating the
accidental appearance of a plain while disc on the screen.
The groove formed by the projections 9, of the sides of the carrier is closed at
its bottom by a metal plate 10.
The bar 4 is curved, so as to permit of the entering slide pressing it back
against the spring 5, with the minimum of resistance and also that the slide when
approaching the bottom of the casing, may be held between the end 11, of the top
rib of the casing, and the convex curve of the bar at 12, and so obviate any
tilting tendency the bar might otherwise exert. The end of the bar projects
forward to follow up the slide to ensure the one on exhibition being correctly in
its place.
The bottom of the carrier, 13, whereon the slides rest, is preferably made
V shaped so that thin slides might always be kept central. The V groove might
be made of metal or other hard substance.
At the outlet end of the carrier, an elastic cushion 14, of any suitable material
may be placed, so that the slides are forced up noiselessly into position.
The metal bar 4 is carried slightly above the projection 8 of the carrier, as shown
at 15, so that it may be pressed by the finger and worked by hand if necessary.
In order to allow the metal plate 10, to project upward clear of the lantern
front the inlet for the slides is so placed that there is a vacant space (an inch or
more usually being necessary) between the incoming slide and the one on exhibition.
On the incoming slide descending clear of the end 11 of the top rib of the casing,
it is immediately moved forward till in contact with the slide on exhibition by
means of the bar 4 and the spring 5.
i
The sides of the carrier at each end are cut away at the top part, so as to
allow the fingers of the operator to insert, (at 16) and to take away (at 17) the
slides.
In this specification I have hitherto described a carrier for taking three slides
only, but in some cases it is more convenient to have a carrier of greater length,
in which case the carrier may be made to contain four or more slides, otherwise
the details are the same.
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. A carrier for lantern slides, operated by means of a spring, substantially as
described.
2. A lantern-slide carrier having a bar actuated by the said spring, which causes
the slides to pass in rotation for exhibition, substantially as described and shown.

page_text: 3. In a lantern slide carrier, a bar, (preferably a curved bar) actuated by a
spring and adapted to move the slides, substantially as described and shown.
4. The improved lantern slide carrier taken as a whole substantially as described
and shown.
LEWIS E. HOPKINS,
Applicant.