Improvements in and relating to Magic Lanterns and to the Manipulation of the same.
Year: 1892

page_text: Date of Application, 3rd Dec., 1892
Complete Specification Left, 4th Sept., 1893-Accepted, 28th Oct., 1893
PROVISIONAL SPECIFICATION.
Improvements in and relating to Magic Lanterns and to the
Manipulation of the same.
I, HENRY SIMPSON of 10 Crooked Lane, Liverpool, in the County of Lancaster,
Lamp Manufacturer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to lanterns used for projecting magnified images of slides
on a screen to illustrate lectures, and the like, and the object of my invention is to
provide means for successively placing in position, in the lantern front, a number
of slides which have been arranged in proper order, to operate the dissolving view
apparatus and to regulate the illumination; each of the three operations being
performed automatically by the one act of the operator.
According to my invention I construct such apparatus as follows;-
I provide a box which I term the slide container large enough to hold the
desired number of slides, say about one hundred, in a single row, one behind the
other. I support the slide container above the lens and lantern front and provide
a spring at the end remote from the condenser, which presses the row of slides
towards the latter. The slide nearest to the condenser is pressed against two side
cheeks whose abutting edges extend below and are in a vertical plane parallel to
the condenser. It will be seen that if this slide be drawn down, being kept pressed
towards the condenser against the said cheeks, it will be brought into proper posi-
tion in front of the condenser; when in this position, it is held by friction and is
just clear of the following slide which in the meantime has been prevented from
descending by the lower edge of the slide container which is only clear of the side
cheeks by a space slightly in excess of the thickness of a slide. If now the upper
slide be drawn down, it will eject the lower slide from position, and the latter then
drops on to a suitable guide which delivers it into a vertical box, which I term the
slide receiver, having a movable bottom supported by a spring, so adjusted, that as
each slide is delivered into the box, the bottom recedes the necessary amount to
accommodate the succeeding slide.
The slides are drawn down in succession from their upper position to the position
in front of the condenser by a pair of side clips which have a vertical reciprocating
motion and which are adapted, as they descend, to engage with the upper edges of
the slides.
The side clips are preferably operated by cranks and connecting rods, the arrange-
ment being such that at each revolution of the crank shaft a fresh slide is brought
into position in front of the condenser.
The dissolving view apparatus may consist of any of the well known forms of
dissolvers, and may be placed in front of the lens or between the latter and the
condenser, and may be operated through any suitable mechanism by the rotation of
the crank shank.
I prefer, however, the following arrangement ;-The dissolver consists of two
over-lapping shutters of coloured or ground glass or the like, hinged from above
and below and placed between the lens and condenser; the spindles which form the
hinges are coupled so that the one operates the other and one of them is operated
by a cam surface or pin on the crank shaft, so that the dissolver is opened and
closed while the slide is in position.
The illumination is regulated by giving the lime a partial rotation each time the
crank shaft revolves; this is effected by giving the requisite movement to a
horizontal pivoted bar which carries an adjustable pawl adapted to operate a
toothed wheel geared to the lime holder.

page_text: I
It will be seen that as one rotation of the crank shaft effects the three desired
operations, it is only necessary for the operator to ensure a rotation of the crank
shaft for each change of slide, and this he may effect in any convenient manner.
prefer however to use a descending weight, (which may conveniently be the iron
gas bottle), as the motive power for actuating the crank shaft, the rotation being
controlled by a pawl or escapement operated directly or by electro-magnetic or
pneumatic means.
When a descending weight is used, a suitable stand is of course provided to carry
the lantern.
If it be desired to heat the slides before they are put in position to avoid con-
densation, the slide container may be placed over the top of the lantern which may
be provided with side chimneys, and the slides, instead of being brought down by
the side clips as described, may be brought down by two endless pitch chains, one
at each side of the slides, operated by the crank shaft and provided with bars
suitably spaced, connecting opposite links of the chain which..
successive slides and bring them into position.
Dated this Second day of December 1892.
engage. with the
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in and relating to Magic Lanterns and to the
Manipulation of the same.
I, HENRY SIMPSON, of 10 Crooked Lane, Liverpool, in the County of Lancaster,
Lamp Manufacturer, 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 lanterns used for projecting magnified images of: slides
on a screen to illustrate lectures and the like, and the object is to provide means
for successively placing in position, in the lantern front, a number of slides which
have been arranged in proper order, to operate the dissolving view apparatus and
to regulate the illumination; each of the three operations. being performed
automatically by the one act of the operator.
According to my invention, I construct such apparatus as follows, reference, being
made to the accompanying drawings in which Fig. I is a side, elevation, Fig..II a
side elevation in medial section, and Fig. III a sectional elevation on the line A. A.
of Fig. II, looking towards the lantern; Figs. IV and V. show a.modification and
will be more particularly referred to hereinafter.
Throughout the drawings, similar parts are indicated by the same, reference
figures.
Each drawing shows the mechanism in normal position, a slide.being in place in
front of the condenser, and the dissolver being open.
1 is the body of the lantern, 2 the condenser, 311 the slide in position for projection
on the screen, and 4.the projecting lens.
6 is a box, which I term the slide container, slightly wider and somewhat deeper
than the slides 3, and sufficiently long to accommodate the number required for an
exhibition, say about one hundred; the sides and bottom are preferably lined with
gláss 5 so as to offer as little friction as possible.
For convenience of carriage, the box 6 is detachably secured to the lantern by
being fitted to slide longitudinally into a groove on top of the bracket 7.
The slides 3 are placed in the box 6, as shown in Fig. II, in a single row, one
behind the other, arranged in proper order, and are pressed toward the right hand
end of the box, which is open, by the sliding block 10, actuated by the light
spring 11 which is sufficiently powerful to overcome the friction between the slides

page_text: and the box. The bottom of the box 6 ends at the point 8, so that the front
slide, for the time being, which abuts against the two side cheeks 9 can be pushed
down by the mechanism to be subsequently described. The slide container 6 is
only partially shown in the drawings as it is essentially the same in construction
as that described and drawn in the Specification of my prior Letters Patent
No. 8185 of 30th April, 1892.
The mechanism for successively pushing the slides into position and ejecting them
is as follows;-
12 is a shaft journalled on the frame of the lantern body and carrying a crank
pin 13 at each side (see Fig. III). These crank pins are connected by the links 14
to the two sliders 15, adapted to slide upon the slotted upright standards. 16, and
fitted with the pivoted clips or pawls 17.
the
The shaft 12 is urged in the direction of the arrow X by a weight (not shown)
hung from the cord 18 wrapped on the drum 19, the force being transmitted through
gear wheels 20 and 21. The click, ratchet wheel and square stem, shown in
Fig. I provide after the usual manner for the winding up of the weight, which may
conveniently be an iron gas bottle as one is generally used in conjunction with a
lantern such as is illustrated.
The rotation of the shaft 12 is controlled by the notch 22 on the rim of the
crank disc 23, which engages with the pawl 24, attached to the armature 25, of the
electro magnet 26, carried on the side of the lantern. When the operator closes
the electric circuit, the armature is attracted, disengages the pawl 24 and the shaft
revolves through one revolution, when it is again arrested as the pawl is allowed to
drop before the revolution is completed; the speed of rotation is regulated, after
the manner common in clock work mechanisms, by the flying vane 27 actuated by
the light train of gear wheels indicated by dotted lines in Fig. 11.
As shown in the drawings, the sliders 15 stand normally at about the middle of
their upward stroke, one slide 3" is in proper position opposite the centre of the
condenser, the preceding slide 31 of the series has been pushed down to the position
shown, and the succeeding slide 3' has dropped out of the slide container 6 and rests
upon 3. Each of the three slides is pressed against the cheeks 9,-31 by the
spring 11, and 31 and 3111 by the strips 28 carried on the presser plate 29 against
which the springs 30 bear. The pressure of the springs 30 is sufficient to sustain
the slides 31 and 3111, the plate is located by the small pins 31 and is of course cut
away opposite to the slide 3". The pressure of the spring 11 may be too great to
allow the slide 3' to follow 311 by its own weight, but this is immaterial to the
action.
When the shaft revolves, the pawls 17 rise to the top of their stroke and by
reason of the weights 32 and stops 33, they assume the position shown in dotted
lines in Fig. III, ready to engage with the slide 31. Upon the down stroke of the
pawls, they bring 31 into proper position, push 3" into the position occupied at
present by 3, and eject the latter, which then falls down the chute 34 into a box
in which the slides pile one on top of the other.
The slides rest within this box on a freely sliding block supported upon a light
spring of such strength that as each slide is deposited, the block descends sufficiently
to accommodate the next. This box is not shown in the drawings, as it is
essentially the same as that described in my said prior Specification.
The dissolver consists of the pivoted overlapping shutters 35, operated by the
levers 36 linked together by the link 37, and their position when closed is indicated
by the dotted lines in Fig. II; these parts are similar to the corresponding parts
described in my prior Specification aforesaid. They are operated by the lever 38
and roller 39 kept in engagement with the cam 40 on the shaft 12 by the spring 41.
During the first quarter revolution of the shaft 12, the dissolver closes, the
pawls 17 meanwhile sliding up idly past the slide 3'; during the next half revolu-
tion, in which the pawls 17 make their down stroke and the slide is changed, the
dissolver remains closed, and during the remaining quarter revolution, the dissolver

page_text: opens, the pawls again sliding up idly in the meanwhile past the slide, into their
original position.
The mechanism for regulating the illumination by slowly rotating the lime block
is shown in Fig. 1; 12 is a ratchet wheel mounted on the lime spindle or one
geared thereto and operated by the pivoted and weighted pawl 43 each time the
latter moves to the right. This pawl is carried on the swinging linkage 44 and
operated by the roller 45 bearing elastically against the cam 40. In order to allow
the lime to be adjusted into focus the ratchet wheel 42 and its spindle and the
paw] 43 are mounted on adjustable frames clamped by the screws 46.
From the description given it is clear that, the slides being in position and the
weight wound up, it is only necessary to momentarily raise and lower the pawl 24
in order to effect all the desired movements, that is to say, to close the dissolver,
change the slide, rotate the lime and finally open the dissolver. The slight move-
ment of the pawl 24 might obviously be effected by pneumatic or mechanical means
instead of electrically as shown, and the shaft 12 might be operated otherwise than
by a descending weight.
The modification shown in Figs. IV and V may be adopted where it is desired to
heat the slides before they are put into position, in order to avoid condensation ;
the slide container 6 is here placed over the top of the lantern, the products of
combustion escaping by the lateral openings 47.
Fig. IV is a side elevation in medial section and Fig. V is a fragmentary sectional
plan
on the line B. B. of Fig. IV; in Fig. IV the cams 40 and 40 and the rollers 45
and 39 which they respectively operate are shown in dotted lines in front of the
plane of section.
The shaft 12 is operated and controlled as already described. Instead however
of drawing the slides down successively by the sliding pawls 17, they are drawn
down by the two pitch chains 48 mounted on the chain wheels 49. The chains are
bridged at proper intervals by the cross bars 50 between which the slides fit freely
and in their descent the slides are elastically pressed against the fixed side cheeks 9¹
by the presser plates 29'. The circumference of the wheels 49 is such that each
complete revolution brings the slides successively into correct position, and when
the slides descend below the lower presser plate they drop away into the chute 34
as the corresponding bar turns round the lower wheel.
The lime operating mechanism is exactly similar to that already described.
The dissolver mechanism is also exactly as before excepting that it is now
operated by a separate quick acting cam 40' instead of the cam 40, having a
deep approximately semi-circular notch into which the roller 39 drops. The
necessity for operating the dissolver quickly in this arrangement arises from the
fact that there is now no idle part in the rotation of the shaft 12 during which
the slides remain stationary, and it is therefore necessary to close the dissolver
immediately the slides commence to move and to open it just before they stop.
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. The improved apparatus for manipulating magic lanterns which consists of a
container adapted to hold the slides and to press the front slide, without supporting
it, vertically, against a fixed vertical guide correctly located in front of the
condenser, and a shaft whose rotation is controlled by the operator and which is
provided with means adapted to draw the slides in succession down the said guide,
to operate the dissolver and to rotate the lime, substantially as described and
illustrated.
2. In apparatus for manipulating magic lanterns and in combination with the
slide container, the means for drawing the slides in succession down the vertical
guide which consist of a pair of reciprocating pawls operated by a rotating shaft
substantially as described and illustrated.