Improvements in Electric Arc Lamps.
Year: 1889

page_text: Date of Application, 1st July, 1889
* Complete Specification Left, 30th Apr., 1890-Accepted, 26th July, 1890
PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lamps.
We THOMAS PHILIP CHRISTOPHER CRAMPTON of 10 Cursitor Street Chancery
Lane in the County of Middlesex Electrician and ALBERT ESSINGER of 11. Hat'on
Garden in the same County Gentleman, do hereby declare the nature of this invention
to be as follows:-
This invention relates to the construction of a very simple cheap and efficient are
lamp occupying extremely little room and capable of giving a large proportion of
work for the space it occupies. We arrange a suitable frame carrying binding
screws for the terminal wires. From one side of the frame
or
and
from one termin il
runs down a rod or metal stem carrying either a copper platina or like block, ball,
disc or the like forming the negative electrode or else carrying a sheath to hold a
carbon or like electrode. To protect the tip of the aforesaid block we may mount
thereon a piece of platina-iridium or the like. Through this frame runs and is secured
thereto a tube of suitable length according to the length of carbon desired to be used
as the positive pole or anode.
Above or below the frame and on the tube we wind a coil as may be suitable such
winding being connected to one terminal on the frame-the other end of the winding
runs to a flat outside iron core piece on the magnet-or to a part of the frame.
Through the magnet and tube runs a solenoid, capable of movement in the tube.
The positive carbon runs through the solenoid. The solenoid carries a flat metal
plate with an adjustable screw placed at one edge.
From lugs facing each other on each side of the flat outside iron core piece on
the magnet or upon each side of the frame we pivot a facing pair of metal plates.
having half. holes formed therein facing each other and through which the positive
carbon rod can fit or pass, or in place of pivotting the facing pair of metal plates to
the core piece or the frame we may connect them thereto by springs one on either
side, such springs being adjustable. The adjustable screw on the flat metal plate
carried by the solenoid also can work in half holes in the facing pair of metal plates
and so limit their motion. The carbon rod runs down to the negative electrode. To
start the lamp a carbon rod is passed through the tube and solenoid till it rests
against the negative electrode. The solenoid sucks up the metal facing pair of plates
gripping the carbon which establishes the arc. As the positive carbon consumes and
the length of the arc increases, the solenoid sinks, letting the metal facing pair of
plates to slightly open so releasing the carbon rod and re-establishing the arc and so
on.
To enable us to use different sized carbons in the same lamp we can fit adjustable
plates on the under surfaces of the pivotted facing pair of metal plates-the facing
ends of such adjustable plates being curved or shaped so as to form when in line
gripping jaws between the adjustable plates, so that the carbon rod then fits the same;
thus by bringing the adjustable plates closer together smaller carbons can be used
and vice versa.
In place of using a negative electrode formed of a solid metal body
and armed with a tip of platina-iridium or like metal, we can use a sheath or tube and
make a carbon rod to pass through the same and be adapted to bear against a
platina-iridium or like ring carried by a moving block or ring on the said tube
through which the carbon passes. Outside this tube slides a ring or weight to which
cords are connected passing over pulleys fixed to the tube. The sides of the tube are
slotted and cords pass over these pulleys and descend to pins passing through slots in
the sides of the tube to a bucket or socket and carrying the negative carbon free and
to rise in the aforesaid tube. As the carbon burns away it is fed up against the
platina-iridium or like ring. In place of using the said ring we may adapt the

page_text: solenoid core to strike a small lever pivotted to a rod or stem passing down and
carrying a pivotted pawl engaging with a tube carrying the lower carbons, by means
of a rack, and so raise the same in consequence of the solenoid striking the small lever
on the rod or stem aforesaid and so the lower carbon is raised. We can also if
desired use a tube passing through the solenoid coil and in which tube the upper
carbon is fixed. The outer fixed tube mounted on the frame carries pulleys over
which cords fastened to the sliding inner tube pass through slots in the outer tube to
a lower moveable carbon holder or tube so that as the upper carbon sinks the lower
one is made to approach it.
Dated this 1st day of Tul.. 1000
T. P. C. CRAMPTON.
ALBERT ESSINGER.
COMPLETE SPECIFICATION.
Improvements in Electric Arc Lamps.
We, THOMAS PHILIP CHRISTOPHER CRAMPTON, of 10 Cursitor Street, Chancery
Lane, in the County of Middlesex, Electrician, and ALBERT ESSINGER of 11 Hatton
Garden, in the said County, Gentleman, 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 relates to the construction of a simple, cheap, compact and efficient
electric arc lamp.
Figures 1 and 2 are front and side elevations respectively of one form of our
invention, certain parts being supposed removed for the sake of clearness.
It consists essentially of two tubes A and B within which carbon or other electrodes
slide freely.
The upper one of these tubes A has fixed to it a hollow iron core 1) which slides
freely inside an outer tube E. The weight of the tube, core and other attachments
being counterbalanced by springs E' E'.
The tube A carries at its lower end a cross piece F to the outer edges of which
are pivotted clutch pieces G G, and a spring H regulated by a screw nut I presses
the jaws of the clutch pieces G G against the carbon C until the tube A, with the
cross piece F and the clutch pieces G G, descends so that the tails of the clutch
pieces rest on catch hooks J J whose lengih is regulated by the screws and nuts as
shewn when this occurs the grip of the clutch pieces G G is relieved and the
carbon slides downwards between them.
The descent of the tube A as the upper carbon consumes, and the consequent feed
of the upper carbon, is effected in the ordinary way by the action of the differential
coils Kand L suitably placed on the outer tube E, K being a coil of thick wire
in circuit with the carbons and La coil of fine wire in shunt to the lamp circuit.
The increased length of arc due to the consumption of the carbons causes less
current to pass through K, and so weakens the upward attraction of the core D,
while it causes more current to pass through L and so strengthens the downward
attraction.
The outer tube E has fixed to its lower end a cross piece M (see plan Fig 4) to
which are attached the hooks JJ and pieces N N of any suitable shape forming the
frame of the lamp. The pieces N N are insulated from the cross piece M and are
joined at their lower extremities to the lower carbon tube B. When the lamp is put
in circuit, the solenoid K lifts the upper carbon striking the arc.
To the top of the carbon tube B is attached by screwing or by a bayonet catch or
hinge a ring or crown (shewn in detail in Figs. 3 and 3) baving a number
(preferably three) of studs o o'o of platinum-iridium or other refractory alloy so
adjusted that they rest outside of the are on the cone formed at the top of the lower
carbon as it consumes.

page_text: The crown is slotted between the studs to allow escape of detached particles of
carbon.
The upward feed of the lower carbon is effected by means of a weight P con-
nected by a chain Q passing over a pulley to a metal piece R sliding freely inside
the tube B, and pushing the lower carbon continually against the studs 0, 0, 0.
Between the metal piece R and the base of the carbon is interposed a conoidal
piece S of porcelain or other insulating material which can project through the
studs o, o, o, when the lower carbon is burned out, thus breaking the arc without
damaging the studs.
The slot T of the tube B is for the purpose of withdrawing the piece R laterally
so that the lower carbon can be introduced or withdrawn through the open bottoni
of the tube B.
U is a guard plate having a central hole through which the upper carbon passes
without contact. This plate prevents the passage upwards of heat and particles of
carbon. It is preferably made of two thicknesses of metal with asbestos between
them, and it is attached to but insulated from the frames N, N.
V and W are the terminals which may be placed where convenient on the frame,
both insulated from the cross piece M, but one W in metallic connection with the
frame N and so with the lower carbon.
The weight Pinay if desired be placed above the frames N N as a ring outside
the coils Kand L, being connected by chains or cords passing over pulleys to the
piece R.
Only one clutch piece G with one relieving hook. J may be used in combination
with a fixed jaw forming part of the cross piece F. Any known clutch may be
attached to the carbon tube A if it is so constructed that the grip is released when
the tube decends below a certain point determined according to the desired length
of arc.
The arrangement may be reversed by fixing the clutch to the cross piece M and
attaching the releasing gear to the tube A as shown in Figures 5, 6, 7, 8, 9.
Fig. 5 is a side view.
Fig. 6 is a plan of the plate F.
Fig. 7 is a plan shewing the clutches and counterbalance.
In Figure 5 M is the cross piece attached to the outer tube E, and is the cross
piece attached to the carbon tube A. gg are the clutch pieces which are pivotted
at a a to arms bbwhich are pivotted at c c and carry adjustable counterbalance
weights d d.
The clutch pieces g g are loosely jointed to slotted holes of a link e which prevents
them from separating; are adjustable releasing studs.
The connecting piece k attached to the cross piece passes through corresponding
half holes in each clutch piece (see plan Fig. 7).
The action of this clutch is as follows:
While the arc is not too long, the clutch pieces are drawn upwards resting on the
head of the connecting piece k, and the weights d d are raised upwards pressing the
clutch pieces against the carbon.
When, on the contrary, the arc lengthens the tube A descends until the releasing
studs bear against the arms whereupon the grip on the carbon is released
allowing the carbon to descend, shortening the arc.
Another form of clutch attached to the crosspiece M is shewn in side view by
Fig. 8 and in plan by Fig. 9.
•
The clutch pieces g' 9' are attached to the cross piece M by flat springs h¹ h',
small studs limiting the range; the connecting piece k' passes through the two
balf holes in g' g' as shewn in Fig. 9.
When then the tube A rises, the connecting piece ¹ draws up the clutch pieces g¹g'
and the flexure of the springs causes g¹ g¹ to grip the carbon; when on the
contrary, A descends in consequence of the lengthening of the arc, the springs
draw back the clutch pieces g'g' allowing the carbon to slip downwards.
h
?

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim in respect of an electric arc lamp is :-
--
1. In combination with the lower carbon holder tube, a crown piece at its top
carrying several refractory studs, and a weight urging upwards a conoidal piece of
insulating material supporting the carbon, so that the coned point of the carbon is
retained in position as it is consumed by bearing against the studs, against which
the conoidal insulating piece is made to bear when the carbon is exhausted, sub-
stantially as and for the purpose set forth.
2. In combination with the upper carbon holder tube having attached to it à core
subject to the differential attraction of two solenoids, a clutch consisting of jaw, which
grip the carbon until by the descent of the tube a certain distance they meet adjustable
stops whereby they are released, allowing the carbon to slip downwards, substantially
as described.
3. The combination of a lower carbon holder such as is referred to in the first
claim, and of an upper carbon holder and clutch such as is referred to in the second
claim with suitable solenoids and framing, constituting an electric are lamp, substan-
tially as described.
10th
Ja of An: 1900
ABEL & IMRAY,
Agents for the Applicants.