Improvements in Arc Electric Lamps.
Year: 1895

page_text: PROVISIONAL SPECIFICATION.
Improvements in Arc Electric Lamps.
We JOHN JAMES MANN and LUCIEN HERMAND both of 21 Boulevard
Poissonnière Paris in the Republic of France Engineers do hereby declare the
nature of this invention to be as follows:-
According to our invention we place the positive carbon and the negative carbon
in are electric lamps each (or either) in a tube these tubes containing spiral or
other springs which press the carbons forward towards the mouths of the tubes.
The carbons are held in the tubes so that only the slightly pointed ends of the
carbons protrude which may be done by means of claws at the mouths of the tubes
or by means of pieces of magnesium or other suitable material.
The two tubes may be fixed facing each other at a convenient distance apart in
such manner that when the electric current is turned on and the arc established by
ineaus of a fusible wire or otherwise, the carbons as they consume will be auto-
matically pressed forward by the springs in the tubes and will thus continue to
feed; or one or both of the tubes may be movable and the arc may be struck and
regulated by means of electro magnets or solenoids or otherwise but the feed of
the carbons will continue to be produced automatically as before.
11
151 1
"
1005
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
We, JOHN JAMES MANN, and LUCIEN HERMAND both of 21 Boulevard
Poissonnière, Paris, in the Republic of France, Engineers, do hereby declare the
nature of our invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
According to our invention we place the positive carbon and the negative carbon
in are electric lamps each (or either) in a tube, these tubes each containing a
spiral spring or equivalent means for pressing the carbons forward towards the
mouths or outlet ends of the tubes. The carbons are held in the tubes so that
only the pointed or reduced ends of the carbons protrude, which may be done
by means of claws at the mouths of the tubes or by means of perforated pieces
of any suitable material.
The two tubes face each other at a convenient distance apart in such manner
that when the electric current is turned on and the arc established by means of
a fusible wire or otherwise, the carbons as they consume will be automatically
pressed forward by the springs or the like in the tubes and will thus continue to
feed; or one or both of the tubes may be moveable and the are may be struck
and regulated or maintained by means of electro magnets or solenoids but the feed
of the carbons will continue to be produced automatically as before.
In the accompanying drawings we have shewn by way of example an arc electric
lamp in which two solenoids of special construction hereinafter described are
ID 17

page_text: arranged to act on the upper carbon of the lamp for maintaining the proper
distance between the carbon points for the maintenance of the arc until the carbons
have been consumed.
Figure 1 is a vertical section taken through the axis of the lamp constructed
according to our invention.
Figure 2 is an elevation of the same but with the casing or envelope in section.
Figures 3 and 4 shew separately one of the tubes provided with carbons.
A is a coil of thick wire and B is a coil of fine wire. The two coils are mounted
loosely on a central tube a provided with a collar a' forming a support for a disc b
on which are the terminals and c¹, the former e being in direct communication
with the dise b and tube a while the latter e¹ is insulated therefrom making contact
with the insulated metallic piece d to which one end of the coil A is connected.
The other end of the coil A is connected to an insulated rod e in electric connection
at its lower end to a rod m insulated from the tube a which rod supports the lower
carbon tube as hereinafter more fully described. One end of the coil B is connected
to the rod e and the other end is connected to a metal plate fin electric connection
with the case C.
in
Within the central tube a is another tube of smaller diameter on which is
fixed a soft iron core i. A socket jis screwed to the lower end of the tube a
and is loose on the tube g. A spring k is interposed between the bottom of the
core and the lower part of the socket j and keeps the core i and tube proper
position relatively to the solenoids A and B. On the tube g below the socket ja
collar gis fixed which can abut against the head of a pin screwed into the
socket j and so stop the descent of the tube g. Through the lower end of the
tube passes a third tube or carbon carrier which is held in position by an
ordinary bayonet joint a.
The socket j receives the aforesaid insulated rod m, which latter carries at its
lower end a bayonet joint y for securing a bracket n in position, through the
lower part n of which passes, and is securely fixed, a tube or carbon carrier
similar to the carrier tube / above.
Any desired number of carbons o o' are introduced into the tubes or carriers l
and respectively, the said tubes being provided with springs bearing at one
of their ends against the end of the tube and at their other end against a plug
bearing on the innermost carbon. The carbons are held in their respective tubes
by sleeves provided with grips or claws p p¹ secured by bayonet joints to the ends
of the said tubes. These sleeves may be made of porcelain metal or any other
suitable material. The ends of the springs adjacent to the carbons each
admit of a small copper rod attached to the plug bearing on the carbon the said
rod serving as a guide and the current is conveyed to the carbons by small spring.
blades u fixed on the tubes near the grips or claws p p¹ and carrying pins
passing through holes in the tubes and bearing on the carbons. These claw
sleeves may be provided with a metal washer or plate which, in the case of the
upper carbon, may be sufficiently large to serve as a reflector for the light.
The carbons follow each other in the tubes in such a manner that their
points are towards the arc and also that the point of the carbon situated at the
exit from the tubes alone projects from the sleeves the jaws of the latter taking
against the conical part of this point.
From the foregoing it will be understood that the lamp can be very readily taken
to pieces and the carbons replaced in position.
By releasing the bayonet joints x and y holding the tubes and the latter are
separated from the lamp. By releasing the bayonet joints fastening the sleeves
and p¹ and removing them the tubes can be fitted with fresh carbons.
By releasing the rod e and unscrewing the socket j the tube g may be taken
out and then the casing can be removed so as to expose the two solenoids A
and B. The disc b may itself be separated from the tube a since it is only
supported against the washer a. The tube g is provided at its upper part with
a cylinder y filled with a suitable liquid such as glycerine for example on the

page_text: surface of which is a pistons made fast to the tube a by means of the cap
pieces. The cylinder 9 and the pistons act as a hydraulic brake in opposition
to any sharp movements of the tube g under the influence of the core-i.
In order to ensure electrical contact between the tube and the conductors for
the upper carbon as well as the contact between the rod m and the part n for the
lower carbon we employ a small spring piston of the kind shewn at t and t¹.
The operation of the lamp is as follows:
.
When the lamp is out of use the upper and lower carbons o and o' are in
contact. When a current of electricity passes through them while in contact it
only passes into the solenoid A (ampère) wound with thick wire which operating
on the core i attracts it, and thus raises the tube g and causes a separation between
the carbon points necessary for striking the arc. At the moment when illumina-
tion takes place the difference of potential at the terminals of the lamp passes
through the thin wire solenoid B (volt) which in turn acts on the core piece i so
as to keep it in such a position that the distance between the points of the two
carbons from each other is kept constant to maintain the arc.
The solenoids A and B thus maintain the distance between the carbons constant
without having to move the latter as they are consumed as is the case in regulators
generally in use. These carbons as has already been described are fed automatically
by means of their springs while they are kept in position at the ends of their
metal tubes or sheaths by means of the sleeves p p. When the carbons have been
entirely consumed the said sleeves p p' form an insulator for cutting off the
current.
A lamp constructed according to this invention is very simple in construction as
all delicate regulating mechanism is dispensed with; the lamps are readily fitted
together and taken to pieces, the carbons may be quickly and easily placed in
position; the lamps being fitted with a supply of carbons may be maintained in
operation for a considerable time, there is great economy in the amount of electrical
energy expended and consequently an equal amount of lighting power is obtained
at a less cost than hitherto.
An are lamp constructed according to this invention may be made in all sizes
and its constituent parts may be made of any convenient forms or dimensions,
while the materials used in their construction will be selected according to the
uses to which they are to be put.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed, we declare that what
we claim is :—
1. An are electric lamp having carbon carriers or tubes in which carbons are
fitted which are continually pressed forward as they are consumed towards the
outlet ends of the said tubes by means of springs, the said carbons being retained
by claws or the like, and having solenoids one wound with thick wire (ampère)
and the other with fine wire (volt) situated around a central tube and operating on
a core piece to which one of the carbon carriers is connected so as to produce and
maintain a proper distance between the two carbons, which are fed forward
automatically substantially as herein before described.
2. In an arc electric lamp the arrangement of the carbons in sheaths or tubes
containing means of propulsion for forcing the said carbons forward continually
towards the outlets from the said tubes where they are retained by means of claws
or the like with bayonet joint attachments substantially as herein before described.
3. In an arc electric lamp the arrangement of carbons in sheaths or tubes with
means for propelling them forward and claws or the like for retaining them as
claimed in Claim 2 in combination with spring plates or blades such as u u¹ to
secure the conducting of the current to the carbons with a bayonet joint for
fastening the said tubes in place and a spring piston such as t. t¹ for ensuring
contact substantially as herein before described.
4. In an arc electric lamp the arrangement on one central tube of two solenoids

page_text: one wound with thick and the other with fine wire for acting by difference of
potential at the terminals of the lamp on a conducting mass formed in one with or
connected to a tube to which is made fast one of the carbon carriers claimed in
Claim 2. substantially as herein before described.
5. In an arc electric lamp the combination of two solenoids on one central tube
and acting on a core piece attached to one of the carbon carriers with a hydraulic
break for deadening or lessening the shocks which might result from a too rapid
action of the coarse wound solenoid, substantially as hereinbefore described.
6. The improvements in arc electric lamps substantially as hereinbefore described
and illustrated in the accompanying drawings.
Dated this 12th day of October 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.