IMPROVEMENTS IN PORTABLE ELECTRIC LAMPS PARTIALLY APPLICABLE TO OTHER PURPOSES
Year: 1883

page_text: LETTERS PATENT to Robert Barlow, of Dalston, in the County of Middlesex,
Surgeon for an Invention of IMPROVEMENTS IN PORTABLE ELECTRIC LAMPS
PARTIALLY APPLICABLE TO OTHER PURPOSES
PROVISIONAL SPECIFICATION left by the said Robert Barlow at the Office
of the Commissioners of Patents on the 25th September 1883.
ROBERT BARLOW, of Dalston, in the County of Middlesex, Surgeon,
MENTS IN PORTABLE ELECTRIC LAMPS PARTIALLY APPLICABLE
PURPOSES
"
" IMPROVE-
TO
OTHER
My invention relates to a combination of devices, whereby in any self-contained
voltaic lamp the electrodes may be withdrawn altogether or in part from the
exciting fluid, without necessitating any considerable enlargement of the base or
battery compartment of the lamp, and whereby an effectual electric contact may
be maintained in the circuit between the lamp and the battery, when the former
be caused to rotate in a horizontal plane. Certain of these devices are also
applicable to other purposes.
The nature of my invention is as follows:-
In a suitable base, divided into compartments radially or otherwise, or in cells
contained in the said base, I place galvanic elements of suitable type for the
generation of electricity. The electrodes are connected up on, and suspended from
a head piece, and from this the leading wires are led up a suitable stem to the
lamp used, preferably of the incandescence type.
The base instead of being continued upwards of the same dimensions or provided
with a rising and falling sleeve-cover of equal dimensions, as is customary in
portable voltaic lamps, is constructed with its upper portion or recess of much
smaller size than the lower, and the upper and outer edges of the electrodes are so
shaped as to enter this recess which may be of domed or coned or other suitable
form, and may be ornamental as to its external covering. Great lightness in the
design of the lamp may thereby be secured while at the same time sufficient
space is provided for raising the electrodes out of the exciting liquid whenever
desired.

page_text: The partial or complete removal of the electrodes from the electrolytes forms a
means of extinguishing or regulating the incandescence of the carbon filament.
The raising and lowering of the electrodes may be effected by a rack and pinion,
provided with a projecting milled head-or it may be effected by a series of
articulated levers or lazy tongs, which are actuated by a screw, provided with a
projecting milled head, working between hinged vertical projections upon the
uppermost pair of the articulated levers; this screw, however, may be replaced by
a suitable rod pressed or pulled by an external button. The movement of the
electrodes or of their actuating mechanism may be utilized to indicate by a suitable
slide or index in the lamp column the position of the electrodes.
A slide or index may be used to indicate whether the lamp terminals are in or
out of contact with the main circuit.
In order to bring the light into any desired position for microscopical work
reading etc, I may provide a hinge joint with the lead wires therein or passing
through, and a contact which shall permit of the rotation in a horizontal plane of
the lamp column, which contact and hinge joint may be used for revolving
electroliers and other moveable parts of electric light fittings. For this rotating
movement I provide a contact of particular construction.
This consists of a core and a sleeve of conducting material each in electrical
connection with a lead wire of opposed polarity. The core and the sleeve are
insulated from one another. The leads joining with the contact, are provided
with a similar contact rotating upon the first named, or they may be provided
with brushes or spring pressed legs, one in contact with the core and one in
contact with the sleeve.
In order to provide a relay, I may provide a switch or plunger, upon the head
piece, which shall allow of one or more of the elements remaining in-operative, and
only brought into operation by means of an external screw, which shall bring the
relay cell or cells into operation when required.
Suitable doors or shutters are provided to obtain access to the batteries.
The lamp bulb is supported on its holder by two spring wire crutches, which
re-act by their elasticity against the looped filament terminals, which are hooked
into the wire leads from the holder, and thus firmly hold the bulb in position,
making at the same time good electrical contact.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, and of
an Order of the Lord Chancellor, filed by the said Robert Barlow in the
Patent Office on the 4th April 1884.
•
ROBERT BARLOW, of Dalston in the County of Middlesex, Surgeon IMPROVE-
MENTS IN PORTABLE ELECTRIC LAMPS PARTIALLY APPLICABLE TO
PURPOSES
OTHER
My invention relates to a combination of devices whereby in any self-contained
voltaic lamp the electrodes may be withdrawn altogether or in part from the
exciting fluid without necessitating any considerable enlargement of the base or
battery compartment of the lamp, and whereby an effectual electric contact may
be maintained in the circuit between the lamp and the battery when the former
is caused to rotate in a horizontal plane, and further whereby the lamp bulb is
held in good elastic contact with the leads. Certain of these devices are also
applicable to other purposes.
In order that the nature of my invention may be fully understood, I proceed to
explain the same with reference to the accompanying drawings. Fig. 1 is the
representation in section of a table-lamp consisting of a galvanic battery in a
suitable case and an attached lamp of the ordinary incandescence type. The lower
part of the base A is sufficiently large to contain the cells (B. B. B) forming the
battery and is much reduced in size in its upper portion C whereby lightness of
design and appearance are rendered practicable. The electrodes (D. D.) of each
cell have their upper and outer edges so shaped as to enter the recess formed by C
when they are raised from the exciting fluids. They are attached to a head-
piece E which is suspended by a hollow screw connection F from the top of C;
and C is surmounted by a distance piece G containing a male screw fitting into
the hollow screw F. Hence when this male screw is turned the head-piece E is
raised or lowered and the electrodes are plunged into or withdrawn from the
exciting fluid to any desired degree and the internal resistance of the battery
lessened or augmented, thus enabling the quantity of the electric current passing
through the lamp and consequently the amount of light produced to be
correspondingly increased or diminished at pleasure. The lamp itself I is affixed
to the distance block G by any suitable holder K, and the current is conveyed by
wires L, L connected with the terminals M. M. of the battery at one end and with
the terminals of the lamp N. N at the other. The dotted lines in the figure show
the position of the electrodes when the lamp is out of action and ready for the
removal of the cells in order to discharge the spent fluids.
It will be understood that instead of removable cells the lower portion of the
base may be divided into cells by means of partitions. The cells may also be in
alignment, tiers and other arrangements instead of being placed radially around a
centre; and the upper portion of the base may be domed or coned or of a fanciful
design such as for example is shown in Fig 2 which is the elevation in outline of a
self-contained electric table lamp in the form of a church.
The raising and lowering of the electrodes may alternatively be effected by a
rack and pinion provided with a projecting milled head; or it may be effected by
means of a series of articulated levers or "lazy tongs actuated by a screw
"
provided with a projecting milled head working between hinged vertical projections
upon the uppermost pair of the articulated levers which screw, however, may be
replaced by a suitable rod pressed or pulled by an external button, or they may be
lowered or raised by means of a cord or other contrivance.

page_text: The movement of the electrodes or of their aforesaid actuating mechanism may
be utilised to indicate by a suitable slide or index in the lamp column the position
of the electrodes. A slide or index may also be used to indicate whether the lamp
terminals are in or out of contact with the main circuit.
Fig 3 shews the form of electric contact I employ for enabling the lamp column
to be rotated in a horizontal plane without interruption of the circuit. It consists
of a central plunger A, and sleeve B, both of conducting metal and insulated from
each other. This is fitted and revolves upon a block of insulating material having
a central cavity and spring contact to receive A, and a strip of metal on the outside
to make contact with B. Alternatively one of the contact pieces may be provided
with brushes or spring-pressed legs bearing respectively upon two metal plates
fitted to the other contact piece as shewn in figure 4. In order to bring the light
into any desired position for microscopical work, reading, etc. I may as shewn in
Fig 5 provide the lamp column with a hinged joint in addition to the contact pieces
already described which contact pieces and hinge-joints may be used for revolving
electroliers and other movable parts of electric light fittings
Figure 6 shews the form of support I employ for holding the lamp bulb itself in
position. It consists of two spring wire crutches which re-act by their elasticity
against the looped filament terminals which are hooked into the wires leading from
the holder and thus firmly maintain the bulb in position and at the same time
make good the electrical contact.
In order to provide a relay I may attach a switch or plunger to the head-piece
of the aforesaid self contained lamp which shall allow of one or more of the battery
elements remaining inoperative until brought into action by means of an external
screw.
Suitable doors or shutters may be provided in the lamp cases in order to obtain
access to the batteries
Having now fully described and ascertained the nature and objects of my
invention and the manner of its performance be it known that what I consider
novel and desire to protect by my letters patent is;-
First, in a self-contained voltaic lamp, the combination of a base and electrodes
so shaped that the upper portion or recess of the base is of much smaller size than
the lower while the upper & outer edges of the electrodes are adjusted so as to
enter this upper portion or recess substantially as specified.
Second, in a voltaic lamp or electrolier or electric light fitting the combination
of a core-and-sleeve contact-piece permitting of rotation in a plane making an
angle with the direction of the electrical circuit or current substantially as
specified.
Third, in a voltaic lamp or electrolier or electric light fitting the combination of
an elastic crutch support for holding the lamp bulb in any desired position &
maintaining good contact with the leads substantially as specified.
In witness whereof I the said Robort Barlow have hereunto set my hand
and seal this First day of April in the Year of our Lord, one thousand eight
hundred and eighty four
Witness
JB BOLEY M.D.
Newnham, Ealing W.
ROBERT BARLOW. (L.S.)