IMPROVEMENTS IN ELECTRIC LAMPS
Year: 1881

page_text: LETTERS PATENT to Cromwell Fleetwood Varley of Bexley Heath in the
County of Kent and Frederick Henry Varley of Mildmay Grove in the
County of Middlesex for an Invention of "IMPROVEMENTS IN ELECTRIC
LAMPS"
PROVISIONAL SPECIFICATION left by the said Cromwell Fleetwood Varley
and Frederick Henry Varley at the Office of the Commissioners of Patents
on the 9th December 1881.
CROMWELL FLEETWOOD VARLEY of Bexley Heath in the County of Kent, and
FREDERICK HENRY VARLEY of Mildmay Grove in the County of Middlesex,
IMPROVEMENTS IN ELECTRIC LAMPS."
14
:―
Our Invention for improvements in electric lighting consists mainly as follows:-
A hollow cylinder of sufficient length to hold the carbon rod is provided with a
spiral spring or propelling weight for the purpose of feeding the carbons. At or
near the feeding end or cap of the cylinder is a roller contact clutch, which is made
to be adaptable for varying diameters of carbon rod, and through which the current
is conveyed to the carbons.
In one arrangement we use an insulated swing arm fixed into the cap, which
carries a fixed opposite carbon pole. To charge this lamp, the swing arm is moved
on one side. The carbon rod or candle is inserted through the roller contact clutch,
and forced into the socket attached to the lower or remote end of the spiral spring,
and this forces back the spring to the length of the carbon to be used. The roller
clutch is provided with a magnetic regulator for determining the length of the arc.
This we prefer to construct in the form of a cylinder of metal placed in a coil
wound with two separate wires, one of which is in the main or arc circuit, and the
other forms part of a derived circuit or shunt of the circuit flowing through
the arc.
This coil is so constructed as to counteract the influence of the arc coil, when
the resistance of the are has arrived at the amount required for best illuminating
effects.
In order that the weights or spiral springs which propel the carbons shall move

page_text: evenly and at a gentle speed, we attach a piston which moves inside the hollow
cylinder one end of which is closed. This piston is preferably constructed as
follows:-
It consists of two or more dises mounted upon a tube or rod and between these
discs, we insert, collars of soft felt or similar substance between which, paper or
suitable material is placed to reduce the porosity. These collars we turn truly in
a lathe by bringing against them a copper or other metal tool heated to a bright
red heat, which burns away the felt until a true cylinder of the requisite dimensions
is formed. This soft felt while forming a plunger or piston or air check moving
easily in the hollow cylinder, is soft enough not to be arrested by any grit that may
have accidentally got into the cylinder. Through this plunger or piston we pierce
a hole, which we prefer to make of a conical form :-a conical wire or spindle, made
to be adjustable is placed in this hole, which being adjusted, allows of the proper
rate of movement of the plunger or piston for carrying or propelling the carbon.
The clutch is preferably constructed as follows:-A U shaped piece of metal
having cross slots carries jointed bars or gimbles. These gimbles are mounted on
horse shoe or suitable springs which press them together.
On each end of the bar of the gimble is mounted a roller, so that the carbon can
be pressed between-then. The carbon-so-mounted_is_free_to_move_right and left,
or laterally. A guide, preferably insulated and placed in front of them directs the
carbon, which is free to move to its proper centre. These four rollers being
mounted upon the above described gimbles, enable the carbons to move in any
direction, and consequently the poles of the carbons by the action of the guides.
(Although the carbon may be crooked) are always directed to the right spot.
In one form of the lamp just described, we use two cylinders and two pistons,
one opposite the other, with similar gimble clutches to hold the carbons:―
These pistons in these tubes, which are closed at one end, are adjusted to move
by means of varying the apertures through the pistons until the two opposing
carbons move in the same ratio as that in which the carbons are consumed by the
electric currents.
Over the lamp we place a glass shade or globe, which is filled with carbonic
anhydride, or carbonic oxide or hydrogen or nitrogen by passing this gas from a
gas holder into the glass shade or cover. The gas we prefer to dry before admitting
it into the globe. In some cases, we fill the glass cover or globe with a vapour of
bydro-carbon.
By dispensing with the magnetic regulator the carbons come in contact and in
this forin sinal incandescent lights can be produced. To prevent the escape and
waste of light radiating upwards, we place rings or rods or preferably hourglass
shaped rods of prismatic section. The upper surfaces of these are coated with
silver, platinum, paladium, or other reflecting metal or other suitable reflecting
substance.
The prisms are so adjusted that the rays radiating from the lamps upward are
shot forward horizontally in the required direction.
In some cases, in place of these prisms, we place a flat or curved surface of glass
covered with bicarbonate of soda, sulphate of baryta or other transparent or
crystalline powder, or carbonate of lead.
In some cases also, we saturate the carbons with paraffin or wax or other hydro
carbon, which under the influence of the beat, evaporates and prevents the
destruction of the carbon.
In another form of lamp we make one or both of the carbons hollow, and pass
through them a jet of gas to surround the carbon rod, to keep away the atmosphere,
and thus retard consumption of the carbons, or we place a tube or casing around
the carbons to supply an annular ring of gas, to envelope the poles for the same
purpose.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Cromwell Fleetwood Varley and Frederick Henry Varley in the
Great Seal Patent Office on the 9th June 1882.
CROMWELL FLEETWOOD VARLEY of Bexley Heath in the County of Kent and
FREDERICK HENRY VARLEY of Mildmay Grove in the County of Middlesex.
"IMPROVEMENTS IN ELECTRIC LAMPS."
Fig. 1 shows the lamp in detail.
Fig. 2 view of swing arm for carrying the fixed opposite carbon, (a continuation
of E (Fig. 1.)
Fig. 3 is a side view of lamp showing the roller clutch.
Fig. 4 plan of lamp with the swing arm E moved on one side, to admit of the
insertion of the carbon rod between the grooves of the roller clutch D D.
Fig. 5, plan of swing arm, showing the lamp for fixing the carbon rod G at the
proper centre.
Fig. 6 plan of coils for actuating the magnetic regulator.
Figs. 7 and 7 show views of two cylinder lamps for regulating the feed of both
carbons.
-
Fig. 8 shows the Invention applied to contact or semi-incandescent lamps.
In Figs. 9 and 10 (and, also in Figure 7) are shown some of the forms of reflectors
or prisins for directing_the_light-in-the-required-manner, either-laterally-or-
downwards.
Fig. 11 a hollow carbon cylinder for the admission of gas.
Fig. 12 is a similar carbon inserted in an outer casing.
Fig. 13, solid carbon rods with an outer casing for supplying the gas.
Fig. 14 general appearance of the lamp of the pendant form.
Our Invention consists subsantially as follows:―
A hollow cylinder A of sufficient length to hold the carbon rod B, is provided
with a spiral spring C or propelling weight C₁ for the purpose of feeding the
carbons B. At or near the feeding end or cap of the cylinder is a roller contact
clutch D which is made to be adaptable for varying diameters of carbon röd, and
through which the current is conveyed to the carbons B.
In one arrangement we use an insulated swing arm E, fixed into the cap F,
which carries a fixed opposite carbon pole G. To charge the lamp, the swing
arm E is moved on one side as shown in Fig. 4. The carbon rod or candle is
inserted through the roller contact clutch D, and forced into the socket II attached
to the lower or remote end of the spiral spring C or weight C and thus forces
back the spring or weight to the length of the carbon to be used. The roller
clutch D is provided with a magnetic regulator J, for determining the length of the
are. This we prefer to construct in the form of cylinders or rods K of metal
placed in a coil or coils L L', wound with two separate wires, one of which is in
the main or are circuit, and the other forms part of a derived circuit or shunt of
the current flowing through the arc.
The coil L is so constructed as to counteract the influence of the arc coil L¹
when the resistance of the arc has arrived at the amounts required for best
illuminating effects.
It is obvious that the rods K K being jointed to the balance arm K¹ when a
current flows through the coil L' by the circuit being completed through the
carbons the rod K is drawn upwards forcing the rod K² downwards, until the
regulator arms J J are forced into the teeth on the rollers D D, forcing them back
and carrying along with them the carbon rod B, establishing the are between B
and G.
When the arc increases in length the coil L which forms part of a shunt or
derived circuit comes into play and by attracting upwards the rod K balances

page_text: the force exerted by the coil L' liberating the magnetic regulators J J allowing
the carbon to slide forward until the power exerted by L is in excess of that
exerted by L, when the arms J J check the movements of the rollers D D, and
thus maintains the arc constant and steady. It is not however necessary to use
two separate coils L and L. One coil with a moving rod may be wound with
two separate wires, one, the shunt circuit being made to counteract the arc circuit.
In order that the weights or spiral springs C which propel the carbons B shall
move evenly and at a gentle speed we attach a piston M, which moves inside the
hollow cylinder A, one end of which is closed. This piston M is preferably
constructed as follows:-It consists of two or more dises mounted upon a tube or
rod N and between these discs we insert collars of soft felt or similar substance O
between which paper or suitable material is placed to reduce the porosity. These
collars we turn truly in a lathe by bringing against them a copper or other
metal tool heated to a bright red heat, which burns away the felt until a truc
cylinder of the requisite dimensions is formed. This soft felt, while forming a
plunger or piston or air check moving casily in the hollow cylinder A is soft
enough not to be arrested by any grit that may have accidentally got into the
cylinder. Through this plunger or piston we pierce a hole, which we prefer to
make of a conical form. A conical wire or spindle P made to be adjustible, is
placed in this hole, which being adjusted allows of the proper rate of movement
of the plunger or piston for carrying or propelling the carbon. The clutch D is
preferably constructed as follows:-A U shaped piece of metal, having cross
slots R carries two jointed bars or gimbles S. These gimbles S are mounted on
horse-shoe or suitable springs T, which press them together. On each end of the
bar of the gimble is mounted a roller D, so that the carbon can be pressed between
them. The carbon so mounted is free to move right and left or laterally. A guide V,
preferably insulated and placed in front of them, directs the carbon, which is free to
move to its proper centre.
These four rollers D, being mounted upon the above described gimbles S enable
the carbon to move in any direction and consequently the poles of the carbon, by
the action of the guide (although the carbon may be crooked) are always directed
to the right spot.
In another form of the lamp just described we use two cylinders A, and two
pistons M M one opposite the other, with similar gimble clutches to hold the
carbons. The lower piston M' is counterweighted by weight C having wires or
lines a attached to same at the lower part passing upwards through stuffing
boxes b over the rollers c into the interior of the cylinder A and are attached to
the upper part of said piston M', so as to propel the carbon upwards. These
pistons M M in these tubes which are closed at one end are adjusted to move by
means of varying the apertures through the piston until the two opposing
carbons move in the same ratio as that in which the carbons are consumed by the
electric currents. Over the lamp we place a glass shade or globe W, which is filled
with carbonic anhydride or carbonic oxide or hydrogen or nitrogen, by passing
this gas from a gas holder into the glass shade or cover.
This gas we prefer to dry before admitting it into the globe.-In some cases we
fill the glass cover or globe with a vapour of hydro-carbon. It is obvious however
that instead of employing a double cylinder, the upper carbon may be carried by a
descending frame, the weight of which would act as the counterweight c. The wire
or line from the frame being made to pass around differential pulley or pulleys
with different speeds, adjusted to feed the carbons at the relative rate in which
they are consumed, the lower cylinder with roller contact clutch and piston or air
check and magnetic regulator being substantially the same as shown in Figs. 1, 3,
6, 7, and 7º.
In Figs. 7 and 7 the contact clutch and magnetic regulator are shown fitted
inside the cylinder A. They may however be of similar construction to that
shown in Fig. 1. By dispensing with the magnetic regulator before described the
carbons come in contact, and in this way small incandescent lights can be produced

page_text: (see Fig. 8). To prevent the escape and waste of light radiating upwards, we place
rings, or coils, or preferably hour glass shaped rods (Fig. 7) of prismatic section.
The upper surfaces of these are coated with silver, platinum paladium, or other
reflecting metal, or other suitable reflecting substance.
The prisms are so adjusted that the rays radiating from the lamps upwards are
shot forward horizontally or in the required direction. In some cases in place of
these prisms we place a flat or curved surface of glass covered with bicarbonate of
soda, sulphate of baryta or other transparent or crystalline powder or carbonato
of lead. The carbonate of lead etc. can be enclosed in between transparent plates,
which are preferably hermetically sealed. In some cases also we saturate the
carbons with paraffin or wax or other hydrocarbon, which under the influence of
heat evaporates, and prevents the destruction of the carbon.
In another form of lamp we make one or both of the carbons hollow (Figs. 11,
12, and 13) and pass through them a jet of gas to surround the carbon rod to
keep away the atmosphere and thus retard consumption of the carbons, or we
place a tube or casing around the carbon (as in Figs. 12 and 13) to supply an
annular ring of gas to envelope the poles for the same purpose.
Having now particularly described and ascertained the nature and object of the
said Invention, and in what manner the same is to be performed or carried out in
practice, we hereby declare that we claim the said Invention of "Improvements in
Electric Lamps" substantially as herein before set forth and described and illus-
trated by the accompanying Drawings, in which the following are particular and
important points or features:-
(1) The roller contact clutch, substantially as and for the purposes hereinbefore
set forth and described.
(2) The swing arm as shown in Fig. 4 as and for the purposes described.
(3) The construction of piston or air check substantially as and for the purposes
described.
(4) The use of balance rods working through the regulator coils as and for tho
purpose described.
(5) The use of two cylinders with pistons and air checks with adjustible contact
clutch regulated to allow the carbons to advance at the relative rate of consump-
tion, as and for the purposes described.
(6) The use of this lamp without magnetic regulator as a contact or semi-
incandescent lamp, as and for the purposes described.
(7) The use of powdered crystalline bodies such as bi-carbonate of soda for
coating reflectors, as and for the purpose described.
(8) The introducing of gas around and through or through the carbons, as and
for the purposes described.
(9) The turning of the felt piston discs or collars used in the air checks; substan-
tially as and for the purposes described.
In witness whereof we the said Cromwell Fleetwood Varley and Frederick
Henry Varley have hereunto set our hands and seal this Ninth day of
June in the year of our Lord One thousand eight hundred and eighty
two
Witness,
W. HILLIER,
21 Cockspur St.,
Charing Cross.
C. F. VARLEY.
(L.S.)
FRED. H. VARLEY. (L.S.)