An Optical Lantern.
Year: 1894

page_text: Date of Application, 19th Dec., 1894
Complete Specification Left, 19th Sept., 1895-Accepted, 30th Nov., 1895
An Optical Lantern.
FRANK ALSTON 211 Ladypool Road Sparkbrook Birmingham Mechanic do
hereby declare the nature of this invention to be as follows:-
This lantern consists of a base board with two upright projections to support the
condenser and objective respectively.
The lime light jet or burner is supported on an universal joint behind the
condenser and is covered by a metal jacket.
The space between the condenser and the objective is left entirely open to
admit the slide carrier which constitutes one of the main points of this invention.
This is constructed with two frames swinging on joints or hinges and so
connected that while one holds a slide in position against the condenser, the other
stands at the side holding the next slide in readiness.
When it is required to change the picture, the connecting rod is moved, this
causes the frames to turn on their hinges so that as one picture leaves the
condenser the next approaches to take its place.
The universal joint which supports the jet consists of a divided ball or cylinder
through the centre of which the gas tubes slide.
This is supported between two cups which on pressure being applied by means
of a screw, or otherwise grip the ball or cylinder which being divided grips the
tubes also, thus fixing the whole in any position required.
Dated this 18th day of December 1894.
.
Ал орысит малог
I, FRANK ALSTON of 211 Ladypool Road, Sparkbrook, Birmingham, Mechanic,
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 relation to optical lanterns for projecting photographic and
other views upon a screen for exhibition, and of that type in which an open space
is left between the objective and the coudensor, whilst surrounding the jets or
burner located at the back of the condensor, is a jacket or screen.
My invention has for its principal objects, first, a universal mounting for the jet
or burner and the lime carrier, and secondly, to facilitate the simultaneous removal
of one view from in front of the condensor, and the presentation of another in the
place thereof.
Figure 1 of the accompanying drawings represents a complete longitudinal
vertical section of an optical lantern fitted with my improvements, showing the
universal mounting of the jet or burner and its cognate parts, also the condensor,
the slide carriers and objective, with the tail board or base carrying the pro-
jections or uprights for supporting the said parts.

page_text: Figure 2 represents a complete topside plan of the lantern, with the mixing
chamber or entrance to the gas jet shown in horizontal section.
Figure 2 represents the two half spheres of the universal joint separately,
showing the concentric semi-circular gaps in their overlapping meeting edges,
wherethrough the gas tubes pass.
Figure 3 represents a vertical section of the lantern taken upon the dotted
lines - Figure 1, looking backwards.
Figure 4 represents a horizontal section upon the dotted lines - Figure 3.
Figure 5 shows the blow through gas burner or jet separately.
The same letters of reference indicate corresponding parts in the several figures
of the drawings.
a is the bed or base-board, with a sliding tail-board b, working upon the middle
of it, and carrying the objective d, through the medium of the upright frame sides
or projections c, adjustable upon the frame rods 6', and the condensor e, through
the medium of the projection or upright f, which also carries at the front of it, the
slide holders g, as hereinafter described.
h is a universal joint mounted upon the rear part a¹, of the base a, through
a projection ', whilst i, i, are the gas tubes, the burner and k a rising and falling
lime carrier, whilst m is the jacket or screen surrounding them.
In the objective part of the lantern, d' is a loose tubular lens carrier, sliding
within an outside sleeve, and adjustably traversed by milled edged wheels d',
mounted at the ends of a spindle d, carrying a pinion d³, which intergears with a
rack d³, upon the said sleeved, whilst a shutter d', is carried by the cap d³. These
component parts are carried by a bracket jacket d', secured to the uprights c₂
which have clip feet c³, embracing the elevated rails or rods 6', and being affixed
thereon by clamping screws e, which contract the said clips upon the rods.
The condensor consists of a fixed frame e' carrying a lens tube e³, connected to
the upright, through lug flanges e³.
The jacket m, is affixed in position by an annular flange m', of it taking into an
annular groove e, in the back edge of the outer tube e¹, of the condensor, and is
there locked by a hook-ended lever n, jointed at n', to a bracket n², carried by the
upright f, and having its axis surrounded by a spring n³, which is compressed, and
the catch disengaged, through the medium of the arm n*.
In the universal joint, are half hollow spheres, with their meeting edges
over-lapping and having concentric semi-circular gaps h, in them wherethrough
the tubes,, leading from the gas cocks, of the gas ways,, pass. h is a
coiled spring located within the middle of the joint, the edges of whose half
spheres are slightly separated from each other in order to effect a binding adjust-
ment., are top and bottom bearing cups, upon the upper one of which the
head, of the adjustment screw hs, which passes through a screw box h¹º, formed
within the cross top member of a frame ", impinges, so that by loosening or
screwing up of the said nut, the gas tubes i, i, constituting as it were the frame to
the burner, are clamped or released.
In the lime carrier, kare uprights, bridged by a cross head k³, and having a
spindle k³, for receiving the lime cylinder, and whose screwed upper part passes
through a screwed hole in the cross head, and is rotated for vertical adjustment
by a turn k, whilst it is stiffened in its movement by a spring k, threaded on the
said pin. This lime-carrier frame has a sliding adjustment upon the gas tubes and
is clamped by the plate k, bridging the said tubes and being drawn down thereon
by the nut k, screwing onto a lower and screwed stem ke, lying between the said
tubes.
In the burner j, the foot end is made in the form of a conical box j', having its
inside filled with wire gauze, and fitting into a conical socket **, formed through
the mixing chamber, terminating the gas tubes i, i².
By mounting the burner and other coguate parts carried by the gas tubes upon
the universal joint h, the jet or jets admit of being adjusted in any position relative
to the condensor.

page_text: The slide carrier 9, consists of two hanging frames 9', 9³, hinged at 9, to a
supplementary frame g³, held to the front side of the upright f, carrying the
condensor, by feather springs 9, and with the said frames coupled together by a
connecting rod g, jointed to crank arms or outstanding parts 97, carried at the
joint ends of the said frames, so that when the connecting rod g, is moved to and
fro, through the medium of a single or double pull and push rod 98, the said
slide-carrying frames move in unison and are alternately presented to and removed
from before the condensor aud within the space between objective and condensor.
Assuming that the slide-carrying frame is in the position represented in
Figure 4, then by pulling the rod 98, in the direction indicated by the arrow, the
frame g, is turned outwardly and away from in front of the condensor, whilst at
the same time the frame g', is turned forwardly and made to take the position
vacated by the frame g³.
By intermittent and simultaneous taking of the frames into and out of position,
there is no time lost between the taking of a shown view froin before the condensor
and the substitution of another in its place.
Having now particularly described and ascertained the nature of ny said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
-
First. In optical lanterns, mounting the gas tubes, or the frame supporting the
jet or burner and the lime carrier, upon a universal joint, substantially as and for
the purpose described and set forth.
Secondly. In optical lanterns, mounting the gas tubes, or the frame supporting
the jet or burner and the lime carrier, upon a universal clamping joint, which
both admits of the said tubes and parts carried by them being universally
adjusted and making a sliding movement, and also clamps the said parts in position
when adjusted, substantially as described and set forth.
Thirdly. In optical lanterns, mounting in front of the condensor, or between the
condensor and the objective, a pair of swinging slide-carrying frames united by
a connecting rod, jointed to outstanding parts of the frame, which rod, when
pushed to and fro, moves the frames in unison and alternately removes one frame
from in front of the condensor and brings the other into the place vacated by
it, substantially as described and set forth.
Fourthly. In the burner, lime carrier and gas tubes of optical lanterns, the
general construction, arrangement and combination of the several parts, sub-
stantially as herein described and set forth.
Fifthly. In optical lanterns, the combination with the duplex slide carriers and
the upright frame or projection supporting the condensor, of the guide frame
rods 61, upon which the objective slides for longitudinal adjustment, substantially
as herein described and set forth.
Sixthly. In optical lanterns, the general construction, arrangement and com-
bination of the whole of the parts, substantially as and for the purpose as
described and set forth.
Dated this for day of September 1890.
Ես
Of September 1899.
FRANK ALSTON,
By Henry Skerrett,
24 Temple Row, Birmingham, Agent for Applicant.