Improvements in Electric Arc Lamps.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lamps.
I, CHARLES OLIVER, of 61, Wilson Street, Finsbury, London, Engineer, do
hereby declare the nature of this invention to be as follows:-
-
This invention relates to electric are lamps and has for its object to obviate or
reduce what is technically known as pumping" when striking the arc, and
furthermore when the arc has been struck-to govern or control the lamp so that
same is not appreciably affected by any rush of current.
In an arc lamp of any usual or suitable construction having one pair (or more)
of solenoids and cores operating in conjunction therewith instead of directly con-
necting such cores by means of a rocking lever or cradle as heretofore according
to my present invention I only connect one of (each pair of) such cores directly
to its cradle or rocking frame or lever while the second core I connect to one
part of a dashpot and either connect the other part of said dash-pot to the other
end of said cradle or lever or I may secure the other said part of the dashpot to
some fixed part of the lamp and loosely attach this end of the cradle or lever
to this core or a connection therefrom i.e. so that a certain amount of play or
movement can take place between said end and said core; for instance :-
(1) I may attach to or form on the lower end of the said second core a piston
or plunger which latter forms part of the dashpot the cylinder of this dashpot
being attached to the last-named end of said rocking cradle or lever in such-
wise that when this said second core is pulled up by its solenoid thereupon it
raises the piston or plunger of the dashpot without rocking its end of the cradle
or lever and the latter being thus released is free to rise and at such moment as
the weight of its core has been removed (i.e. lifted) therefrom consequently the
other end of the lever or cradle will be caused to descend by the weight thereon
of the shunt core (a second and separate dashpot or equivalent offering a gradual
resistance thereto may be fitted) and thereby the arc is struck and thereupon the
cradle or lever comes to rest and the second core descends in its solenoid (its
sudden descent being resisted by the dashpot) until it or its plunger comes to rest
against the cylinder bottom or against a stop provided on said lever cradle or
dash pot for instance said plunger may come to rest on the bottom of its pot,
and the parts are brought into a normal condition and there maintained while
the current flows steadily through the lamp.
The weight of the said second core is such that it is sufficient to overcome
the normal pull of its solenoid. Or (2) I may attach the said second core to the
eylinder of the dashpot and attach the piston thereof to some fixed part of the
lamp (or attach the said core to the plunger and attach the cylinder to some
fixed part of the lamp) and then connect the said rocking lever or cradle to said
core in suchwise that there is a certain amount of play or movement between them
for instance I may form or arrange a vertical slot (of sufficient length) in or on
said core or plunger (that is at a point between the solenoid and the cylinder)
while the said rocking lever or cradle carries a pin or bar adapted to slide in said
slot or vice versa) or other equivalent or suitable means may be employed to

page_text: suitably connect said cradle or lever to said second core and dashpot so as to
permit the aforesaid play or if desired the parts need not be connected but
simply arranged in suchwise that the core can rise off the cradle but on its descent
will engage and rest upon or bear down the said rocking lever or cradle.
The dashpot (to which the said second core is connected) is provided with an
air inlet valve or valves so arranged as to permit the said core to rise freely with-
out retardation while the descent of said core would be regulated by said dashpot.
It is obvious that the hood or cylinder of said dashpot may be attached to the
core and the plunger to the lever or cradle.
Dated this 15th day of August 1898
TONGUE & BIRKBECK,
Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.
I, CHARLES OLIVER, of 61, Wilson Street, Finsbury, London, Engineer, 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 electric arc lamps and has for. its object to obviate
or reduce what is technically known as pumping" when striking the are; and
furthermore when the arc has been struck-to govern or control the lamp so
that same is not appreciably affected by any rush of current.
In an are lamp of any usual or suitable construction having one pair (or more)
of solenoids and cores operating in conjunction therewith instead of directly
connecting such cores by means of a rocking lever or cradle as heretofore according
to my present invention I only connect one of the pair of cores directly to its
cradle or rocking frame or lever while the second corc of said pair
is free to disengage itself that is said second core is free to rise
off said cradle without lifting the latter therewith for which purpose I may
either connect said second core direct to one part of a dashpot and either connect
the other part of said dashpot to the other end of said cradle or lever or I may
secure the other said part of the dashpot to some fixed part of the lamp and
loosely attach this end of the cradle or lever to this core or a connection there-
from .e. always so that a certain amount of play or movement can take place
between said cradle end and said core: for instance; -
(1) I may attach to or form on the lower end of the said second core a piston or
plunger which latter forms part of the dashpot the cylinder of this dashpot being
attached to the last-named end of said rocking cradle or lever in suchwise that
when this said second core is pulled up by its solenoid thereupon it raises the
piston or plunger of the dashpot without rocking its end of the cradle or lever
and the latter being thus released is free to rise and at such moment as the weight
of its core has been removed (i.e. lifted) therefrom consequently the other end of
the lever or cradle will be caused to descend by the weight thereon of the shunt
core (a second and separate dashpot or equivalent offering a gradual resistance
thereto may be fitted) and thereby the arc is struck and thereupon the cradle or
lever comes to rest and the second core descends in its solenoid (its sudden descent
being resisted by the dashpot) until it or its plunger comes to rest against the
cylinder bottom or against a stop provided on said lever cradle or dashpot for
instance said plunger may come to rest on the bottom of its pot, and the parts

page_text: are brought into a normal condition and there maintained while the current
flows steadily through the lamp.
Or (2) I'may attach the said second core to the cylinder of the dashpot and
attach the piston thereof to some fixed part of the lamp (or attach the said core to
the plunger and attach the cylinder to some fixed part of the lamp) and then con-
nect the said rocking lever or cradle to said core in suchwise that there is a certain
amount of play or movement between them for instance I may form or arrange a
vertical slot (of sufficient length) in or on said core or plunger (that is at a
point between the solenoid and the cylinder) while the said rocking lever or cradle
carries a pin or bar adapted to slide in said slot (or vice versa) or other equivalent
or suitable means may be employed to suitably connect said cradle or lever to
said second core and dashpot so as to permit the aforesaid play or if desired the
parts need not be connected but simply arranged in suchwise that the said second
core (i.e. the main core) can rise off the cradle but on its descent will engage and
rest upon or bear down the said rocking lever or cradle.
The weight of the said main core is such that it is sufficient to overcome the
normal pull of its solenoid and just sufficient to effect the necessary regulation
of the carbons.
It is obvious that the hood or cylinder or said dashpot may be attached to the
core and the plunger to the lever or cradle.
In the accompanying drawings I have illustrated an arc lamp constructed and
arranged to act according to my present invention.
Fig. is a view in elevation-partly in section-of the interior mechanism of
an arc lamp constructed according to my present invention.
Fig. 2 is a view at right angles to Fig. 1; the lamp illustrated being a double
lamp.
A B are the pair of solenoids in which are operated the cores ab to control the
carbons in the said lamp, the core b is the aforesaid second or "main core
"and
has loosely pivotted to the inner end thereof a piston or plunger-head e adapted
to fit and slide easily in the tube or lining B in the solenoid B which tube B
thus forms the dashpot cylinder, while the other or outer end of said core or rod b
passes freely through a sleeve & pivotted at the point d to one end of the
rocking frame or cradle while a spring e is interposed (on the rod b) above the
cradle said spring being held in position by the weight f on the core bor in
other suitable manner.
Thus a dashpot or similar action is caused in the solenoid B with respect to
the movement of the core b therein.
The core a (c. the shunt core) is provided with weight thereon and said
core is pivotted at a to the cradle and below same is attached to the
cylinder of a dashpot the piston-rod of the piston j-of which dashpot is
pivotted to a fixed part y of the lamp.
u is connecting rod from the end of the cradle (to which it is pivotted at u¹)
to the clutch lever to which latter it is pivotted at the clutch mechanism w
operated by said lever and controlling the upper-carbon rod holder z being of
any well-known or suitable form by which the feed is controlled as said clutch or
device w is operated by or from said cradle or rocking frame as is well under-
stood and such clutch or device won the rod z need not therefore be herein
further described.
is the lower-carbon rod holder which is controlled and operated (raised and
lowered) by means of a flexible connection = passing over the pulley 23 and
connected to the upper end of the upper-carbon rod holder z.
The operation is as follows:-
Before the current is switched on the weight f on the core 6 rests through the
medium of the spring e upon the swinging sleeve & pivotted at d to the end t
of the cradle as aforesaid and in this position the core 6 is quite free to rise
without moving the cradle.

page_text: Immediately the current is turned on it will flow through the solenoid B and
consequently the core will be drawn into said solenoid B and as said core b
can slide freely through the sleeve d pivotted in the cradle & as aforesaid conse-
quently the core 6 will be drawn up without moving the cradle a and thereby
leaves the end of the cradle a free to rise whereupon the weight y on the
core a will bear down the other end of the cradle and thus lift the connecting
rod u which latter through the clutch mechanism v w will consequently now
therefore lift the upper-carbon rod holder z and simultaneously lower the lower-
carbon rod holder and thus strike the arc the ascent of the core being
regulated by the dashpot action of its piston-head c in the cylinder B¹ as also the
descent of said core b; and also the too sudden descent of the core a and weight g
thereon is regulated by the dashpot hij at the lower end of said core a; while
the weight of the core 6 and its weight f as same come to bear again upon the
end of the cradle x is (gradually) received by the latter through the medium
of the spring e.
If during the burning of the lamps any sudden rush of current takes place the
carbons will not (i.e. cannot) be violently drawn asunder owing to the aforesaid
construction and arrangement of the regulating mechanism.
This lamp is specially applicable to short series circuits.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:
1. In an electric arc lamp-mounting the main core in suchwise with respect
to the rocking frame or cradle of the regulating mechanism that the said main
core can rise independently of the cradle substantially as and for the purposes
specified.
2. An electric arc lamp having the core of its main solenoid combined and
arranged in suchwise as to be adapted to be lifted independently of and without
it lifting its end of the rocking frame or cradle of the regulating mechanism.
3. The improved arrangement and construction of the regulating mechanism
of electric arc lamps substantially as and for the purposes herein before specified.
4. Electric are lamps having the several parts thereof constructed combined
and arranged to act substantially as and for the purposes hereinbefore described
with reference to and as illustrated in the drawings hereunto annexed.
Dated this 15th day of June 1899.
TONGUE & BIRKBECK,
31, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.