Improvements in Portable Electric Safety Lamps and Batteries, and Appliances for Charging them.
Year: 1892

page_text: Date of Application, 2nd Nov., 1892
Complete Specification Left, 30th Mar., 1893-Accepted, 6th May, 1893
PROVISIONAL SPECIFICATION.
Improvements in Portable Electric Safety Lamps and Batteries, and
Appliances for Charging them.
We, THE EDISON & SWAN UNITED ELECTRIC LIGHT COMPANY LIMITED,
of 100 Victoria Street, Westminster, in the County of Middlesex, and EDWARD
ALFRED GIMINGHAM of the said Company of Ponders End, in the County of
Middlesex, Electrician, do hereby declare the nature of this invention to be as
follows:-
:-
Our invention relates to electric lamps and secondary electric batteries combined
together to form portable lamps of a kind such as is described in Swan's Specifica-
tion No. 1999 of 1886.
The chief objects which we have in view are to make such provisions for safety
that lamps of this kind may be used in mines, magazines or other dangerous
situations and to provide appliances by which numbers of such lamps can be con-
veniently and rapidly charged.
The battery of a lamp according to our invention consists of several cells, such
as three or four, each preferably of cylindrical form, and made of xylonite.
All these cells are fixed on one base, and have a cover common to them all faced
with caoutchouc or other suitable packing and pressed down on them by a nut on.a
central bolt which passes through the base and the cover.
The several cells, thus grouped together as if in one piece, are put into a case
which may be of wood, and which has its bottom attached to the central bolt and
its cover secured on a ring of caoutchouc or packing by a second nut on an
upwardly extended and smaller part of the central bolt. To the cover of the case
is jointed a handle by which the whole can be carried. An incandescent lamp
presents itself at the side of the case within a glass of basin form, and it has its
wires connected to the battery by contacts of the following description:
The plates in the battery cells are connected in series to two lead plugs, one
placed at each side of the battery. Each of these plugs projects downwards from
a socket containing a caoutchouc or other spring bearing against the plug. In the
case for receiving the battery there are two lead stops, which are connected to the
wires of the lamp, and which present their faces in such positions that when
the battery is put into the case the lead plugs of the battery rest upon those lead
stops. When the cover of the battery is screwed down its plugs, being pressed by
springs, can yield a little, but they make sound electrical contact with the stops in
the case and thus by the mere insertion and fixing of the battery in the case, the
lamp is put in circuit with the battery. Lead is employed as the material for the
contact plugs and stops as it is not attacked by the liquid, dilute sulphuric acid,
which is employed in the cells.
As a safety switch we employ the following device. One of the lamp wires is
divided and the two ends at the division are sealed at a little distance from each
other in a glass bulb which is exhausted of air and contains a small quantity of
mercury.
When the lamp is held upright or nearly so, the mercury lying on the two wires
makes electrical connection, closing the lamp circuit, but by inclining the lamp
more or less the mercury flows away from the wires opening the circuit. The bulb
of this switch is preferably made in the form of a retort or of a bent tube with a
bulbous cavity at each end, so that, on sufficiently inclining the lamp, the mercury
can be made to flow into the opposite cavity and will remain there, keeping the
lamp circuit open, even when the lamp resumes its upright attitude; but, by

page_text: shaking the lamp, the mercury may be made to flow back to the cavity in which
the wires present themselves and so to close the circuit again. The switch thus
constincted serves to open or close the circuit with safety, as there is no external
sparking possible, and it always opens the circuit and extinguishes the lamp when
it is much inclined. For charging a number of the batteries, we fix on a suitable
framing a number of pairs of contact stops each pair corresponding with the pair
in the lamp case, and we connect by a conductor the first stop of the first pair and
the last stop of the last pair to the terminals of a dynamo electric machine or other
suitable electric generator; we also connect the last of each pair of the stops by a
conductor to the first of the next pair in order.
We, place a number of the lamp batteries with their spring plugs resting on
those stops, and thus they become all connected in series so that they can be charged
altogether from the dynamo machine or generator.
7
When they are thus charged they are lifted off from the contact stops and placed
in the lamp cases in which they become at once connected to their respective
lamps, unless the mercury of the switches be in position for opening the respective
circuits.
Dated this and do of 1000
ABEL & IMRAY,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Portable Electric Safety Lamps and Batteries, and
Appliances for Charging them.
We, THE EDISON & SWAN UNITED ELECTRIC LIGHT COMPANY LIMITED
of 100 Victoria Street, Westminster, in the County of Middlesex, and EDWARD
ALFRED GIMINGHAM of the said Company of Ponders End in the County of
Middlesex, Electrician, 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:―
Our invention relates to electric lamps and secondary electric batteries combined
together to form portable lamps of a kind such as is described in Swan's Specifica-
tion No. 1999 of 1886.
The chief objects which we have in view are to make such provisions for safety
that lamps of this kind may be used in mines, magazines or other dangerous
situations and to provide appliances by which numbers of such lamps can be con-
veniently and rapidly charged.
Fig. 1 of the accompanying drawings is a vertical section on the line X X of
Fig. 2 which is a sectional plan of an electric safety lamp according to this
invention.
Fig. 3 is a part elevation and part section on Y Y of Fig. 2.
Figs. 4 and 5 show two forms of mercury switch.
Fig. 6 is an elevation of the appliance by which many of the lamps are
simultaneously charged.
The battery consists of several cells A of which four are shown each, preferably
of cylindrical form and made of xylonite or other suitable material. All these cells
are fixed on one base B and have a cover C common to them all faced with
caoutchouc or other suitable packing D and pressed down on them by a nut E on a
central bolt F which passes through the base and the cover.
The several cells, thus grouped together as if in one piece, are put into a case G
which may be of wood or other suitable material, and which has its bottom attached
to the central bolt and its cover H secured on a ring of caoutchouc or packing by a
second nut e on an upwardly extended and smaller part of the central bolt F. To
the cover of the case is jointed a handle h by which the whole can be carried. An
incandescent lamp L presents itself at the side of the case within a glass K of

page_text: Each of
basin form and it has its wires connected to the battery by contacts of the following
description. The plates in the battery cells are connected in series to two lead
plugs P P one placed in a xylonite tube at each side of the battery.
these plugs is connected by a helical lead wire to another plug Q Q' which projects
downwards from the xylonite or other tube.
In the case for receiving the battery there are two lead stops R R' which are
connected to the wires of the lamp, and which present their faces in such positions
that when the battery is put into the case the lead plugs Q Q' of the battery rest
upon those lead stops R R¹.
When the cover of the battery is screwed down its plugs Q Q' make sound
electrical contact with the stops in the case and thus by the mere insertion and
fixing of the battery in the case the lamp is put in circuit with the battery. In
some cases we fit the plugs Q Q' to slide a little in the xylonite or other tubes with
caoutchouc or other springs above them so that they can yield a little. Lead or
suitable lead alloy is employed as the material for the contact plugs and stops as it
is not attacked by the liquid, dilute sulphuric acid, which is employed in
the cells.
As a safety switch we employ the following device shown in Figs. 4 and 5. One,
of the lamp wires W is divided and the two ends at the division are sealed at a
little distance from each other in a glass bulb S which is exhausted of air and
contains a small quantity of mercury.
When the lamp is held upright or nearly so the mercury lying on the two wires
makes electrical connection, closing the lamp circuit, but by inclining the lamp
more or less the mercury flows away from the wires opening the circuit. The bulb
of this switch is made in the form of a retort as shown in Fig. 5 or of a bent tube
with a bulbous cavity at each end as shown in Fig. 4, so that, on sufficiently inclining
the lamp the mercury can be made to flow into the opposite cavity and will remain
there keeping the lamp circuit open, even when the lamp resumes its upright
attitude; but, by shaking the lamp, the mercury may be made to flow back to the
cavity in which the wires present themselves and so to close the circuit again. The
switch thus constructed serves to open or close the circuit with safety as there is no
external sparking and it always opens the circuit and extinguishes the lamp when it
is much inclined. For charging a number of the batteries as shewn in Fig. 6 we fix
on a suitable framing T a number of pairs of contact stops rr each pair corresponding
with the pair R R in the lamp case and we connect by branch conductors U U₁
the first stop of the first pair in each row and the last stop of the last pair in each
row to the terminals of a dynamo electric machine or other suitable electric
generator; we also connect the last of each pair of the stops by a conductor to the
first of the next pair in order.
2°
We place a number of the lamp batteries X with their plugs QQ¹ resting on the
stops and thus all in each row become connected in series so that they can he
charged all together from the dynamo machine or generator.
When they are thus charged they are lifted off from the contact stops and placed
in the lamp cases in which they become at once connected to their respective
lamps, unless the mercury of the switches be in position for opening the respective
circuits.
The conductor from each row of contact stops may have in its course a lamp Y
to show by its incandescence when the cells are sufficiently charged whereupon the
row can be cut out of circuit by means of a switch key Z.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In a portable electric safety lamp, the combination in a casing of several
secondary battery cells held between a base and cover by a central bolt, their
electrodes being connected in series to suitable metal plugs attached to the cells
resting on corresponding stops which are attached to the casing and are connected

page_text: through a suitable switch to the wires of an incandescent lamp arranged at the side
of the casing, substantially as described.
2. For a lamp such as is above referred to, a switch consisting of an exhausted
bent glass tube or vessel containing mercury and having the ends of a divided part
of one of the lamp wires sealed into it at some distance apart substantially as
described with reference to Figs. 4 and 5.
3. For charging a number of cells for lamps, such as are above referred to, a frame
having a number of contact stops corresponding with those in the lamp casings,
arranged in rows and connected to the terminals of a suitable electric generator
substantially as described with reference to Fig. 6.
Dated this 30th day of March 1893.
ABEL & IMRAY,
Agents for Applicants.