Improvements in Electric Flash Signalling Lanterns and Apparatus in connection therewith.
Year: 1890

page_text: Date of Application, 13th Mar., 1890.
Complete Specification Left, 13th Dec., 1890-Accepted, 28th Feb:, 1891
PROVISIONAL SPECIFICATION.
Improvements in Electric Flash Signalling Lanterns and Apparatus
in connection therewith.
WILLIAM STEPNEY RAWSON, of 88, Queen Victoria Street, Electrician, &
CHARLES SCOTT SNELL, of Culver Park, Saltash, Cornwall, Engineer, do hereby
declare the nature of this invention to be as follows:-
The invention relates to improvements in electric flash signalling lanterns and
apparatus in connection therewith & is intended to enable a vertical sliding action
of the extinguishing shutter or shutters to be produced by electrical means
sufficiently rapidly for signalling purposes. We employ two solenoids so that the
same core is suitable for both. One of these solenoids is wound with a few turns of
thick wire & the other with many turns of thin wire. The former is arranged so
that when the light is obscured it is in circuit with the lamp & reduces its intensity
the latter is arranged to work in shunt to the lamp & it is this solenoid which pulls
down the shutter against the action of a spring or similar device which assists to
raise the shutter when the current is broken in the lower solenoid. To avoid
sparking in the switch which is employed with the lantern the two solenoids should
be momentarily in action simultaneously. The extinguishing shutter which may
be either opaque or some coloured transparent material is conveniently attached to
the core of the solenoid & is as light as possible.
We may arrange two or more concentric shutters of various colours & one opaque
& by suitable mechanical & electrical devices we may arrange that the core of the
solenoid only engages with the particular shutter which it is required to use.
In this way flashes of alternate coloured and white light may be produced. We
add the necessary switches & cut outs to enable signalling to be carried on con-
veniently.
f
r
COMPLETE SPECIFICATION.
Improvements in Electric Flash Signalling Lanterns and Apparatus
in connection therewith.
WILLIAM STEPNEY RAWSON, Electrician, of 88, Queen Victoria Street, E.C.,
in the County of Middlesex, London, and CHARLES SCOTT SNELL, Electrical
Engineer, of Culver Park, Saltash, Cornwall, 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 :—
The invention relates to improvements in electric flash signalling lanterns and
apparatus in connection therewith and is intended to enable a vertical sliding action
of the extinguishing shutter or shutters to be produced by electrical means
sufficiently rapidly for signalling purposes.
1.
References made to the drawings annexed.
Fig: is a vertical-section, Fig. 2 an elevation and Figs. 3 & 4, horizontal sections
(at UV and W-X respectively, see Figs. 1 and--2) of a lantern constructed in
accordance with our invention. Fig. 5 is a diagram of the electrical connections
and plan of the switch employed. Fig. 6 is a side elevation of the switch. Fig. 7
is a plan with electrical connections and Fig. 8 is a side elevation of a supple-
mentary switch for use where several shutters are employed. Fig. 9 is a vertical
T

page_text: section showing three shutters in position and Fig. 10 is a detail showing how the
lifting arms are caused to gear with the shutters.
In Fig. 1 it will be seen that we employ two solenoids marked throughout the
plans A & B the same core C being suitable for both. The upper solenoid is wound
with a few. turns of thick and the lower with many turns of thin wire. The former
is arranged so that when the light is obscured it is in circuit with the lamp and
reduces its intensity and its action as a solenoid is to raise the core C and carry the
opaque shutter D up around the lamp the filament of which is marked E. The lower
solenoid B is arranged to work in shunt with the lamp, see Fig. 5 and it is this
solenoid which pulls down the shutter against the actions of springs F; F which
assist to raise the shutter when the current in the lower solenoid is broken or
has such a resistance (as shown at G in Fig. 5) put in circuit as to reduce its effect
to a minimum.
To avoid or minimise sparking in the switch which is employed with the lantern
the two solenoids should be momentarily in action simultaneously.
The extinguishing shutter which may be either opaque or of some coloured trans-
parent material is conveniently attached to the core as shown in Fig. 1 and should
be as light as possible. We may arrange two or more concentric shutters of various
colours and one opaque as shown in section in Fig. 9. The opaque shutter is kept
outside and the core attachment H carries two skeleton arms II with pins J Jat
their extremities working in suitable gaps in the shutters as shown in Fig. 10 the
pin J if raised directly will pick up the outer or opaque shutter D if turned to the
right it will engage with and pick up the middle shutter say coloured red if turned.
to the left it will lift up the inner-shutter say coloured-green. In this way flashes
of alternate-coloured and white lights may be produced. This operation of changing
the colour of the light is effected by the supplementary switch shown in Figs. 7 & 8.
It will be seen that if the key marked "red" is depressed the positive pole of
dynamo is in connection with key K and the negative with L producing a current
in the electro magnets Q in such a direction as to cause the upper poles to be N
and to swing the permanent magnet P from left to right and thus acting on the
arms II to put the whole in a position to work the middle or red shutter. If now
the other switch be operated to raise this shutter alternate flashes of white and
coloured light will be shown.
The main switch is fitted with a handle that rotates by the action of a spring so
as to break the dynamo circuit as soon as the hand is released.
It will be seen that with two switches or a combined switch the raising and
lowering of the shutters may be performed with one hand whilst a touch of the
finger upon the red or green key determines the character of the colour to
be used.
It is clear that by the movement of one hand the flashes of light may be produced
while with the other the colour of the light shown may be determined.
Having now particularly described and ascertained the matter of our inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is-
1. In an electric signal flashing lamp the employment of two concentric solenoids
which have a common core and actuate a shutter, opaque or coloured, substantially
as described and for the purposes set forth.
2. In an electric signal flashing lantern, as described in claim 1, the employment
of springs acting in opposition to one another and in combination with the core for
the purposes set forth.
3. In an electric signal flashing lantern, as described in Claim 1, the arrange-
ment of electrical circuits substantially as described and for the purposes set
forth.
4. In an electric signal flashing lantern the method by which the shutter used
can be altered, from opaque to coloured, at the will of the operator, by electrical
action substantially as described.

page_text: 5.-The combination and arrangements of the parts of the lantern and operating
switches substantially as described and for the purposes set forth.
December 13th 1800
W. STEPNEY RAWSON.
C. SCOTT SNELL.