Improvements in Electric Arc Lamps.
Year: 1896

page_text: Date of Application, 25th July, 1896
Complete Specification Left, 14th May, 1897-Accepted, 19th June, 1897
Improvements in Electric Arc Lamps.
We, EDWARD JONES, and ALBERT EDWARD JONES, Engineers, and GEORGE
KYNOCH AND COMPANY LIMITED, Manufacturers, all of Lion Works, Witton, in
the County of Warwick, do hereby declare the nature of this invention to be as
follows:-
This invention consists of improvements in electric arc lamps, our object being
to provide more simple feeding appliances or means for advancing the carbons
during combustion, than exists with the arc lamps at present in general use.
Our improved feeding apparatus consists essentially of a high resistance magnet
circuit in shunt to the main circuit, so arranged that during the consumption of
the carbons the increasing resistance of the are increases the strength of the high
resistance circuit, and such increased strength of the shunt magnets, by attracting
an armature, draws back or compresses spring until the shunt magnet is
ultimately broken, when the compressed spring is liberated to perform the work
of feeding or advancing the carbons.
In one convenient application of our invention the armature is mounted on a
lever having a pawl at one end which engages the teeth of a ratchet wheel and
actuates a screwed rod supporting the top or positive carbon holder.
When the
ratchet is turned or revolved by the pawl the positive carbon holder is advanced
towards the lower or negative carbon, and such action continues until the normal
resistance of the arc is re-established, when the feeding movement is arrested until
further consumption of the carbons.
The high resistance circuit is made complete by a contact which is always
maintained except when the armature is drawu towards the magnet against the
resistance of the regulating spring, when contact is broken to permit of the feeding
operation. The contact may take the form of a piston carried in the pawl lever
hereinbefore described, or instead of a piston we sometimes employ a sliding switch
actuated by such lever.
We preferably dispense with the use of magnets or other appliances for striking
the arc in the construction of our improved lamps. We point or sharpen the upper
or positive carbon, and in trimming the lamp the carbons are not placed in contact.
On the current being admitted it passes by way of the shunt circuit, and causes the
feeding mechanism to be instantly operated, thus advancing the positive carbon
until it is brought into contact with the negative carbon, when the current instantly
passes by the main circuit and consumes the sharp point of the positive carbon and
so forms the arc. The carbons are kept from contact except during the feeding
operation hereinbefore described, and do not rest upon each other as in ordinary
arc lamps.
When employing an arc striking arrangement in connection with our lamp we
use a magnet or magnets forming part of the main circuit for attracting an armature
which is preferably connected to a lever arranged to operate the positive carbon
holder by means of a screwed rod, and thus to move the carbon to a sufficient
extent to establish the arc and to maintain the same in such position during the
whole time that current is passing. The feeding is effected entirely by means of
the shunt circuit herein before described.
The screwed rod herein before described of the feeding mechanism engages or

page_text: gears with a segmental nut, the parts or segments being held together by a spring
clip that can be readily opened to release the nut for permitting of its being moved
freely up or down the rod during trimming of the lamp.
In the application of our invention to a double lamp or one arranged to carry
two pairs of carbons in such a manner that the second pair are brought into use
after the first pair is burnt out, we employ a second positive carbon holder working
on or supported by the rod which supports the first holder. The second pair of
carbons are kept out of contact and out of gear with the feeding mechanism until
required by means of a forked lever, and such lever also holds open the nut and
retains the same together with the carbon holder in one fixed position.
When the first pair of carbons are on the point of being burnt out the continued
advance of the positive carbon holder carries forward a sleeve connectel by a rod
with the forked lever, and the movement of such lever puts the split nut of the
second positive carbon holder into gear with the feeling mechanism, and the second
positive carbon is thus brought into use.
Dated this 24th day of Jule 1896
MARKS & CLERK,
18 Southampton Buildings, London, W.C., and
13 Temple Street, Birmingham, Agents for the Applicants.
Improvements in Electric Arc Lamps.
We, EDWARD JONES, and ALBERT EDWARD JONES, Engineers, and GEORGE
KYNOCH AND COMPANY LIMITED, Manufacturers, all of Lion Works, Witton, in
the County of Warwick, 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 consists of improvements in electric arc lamps, our object being
mainly to provide more simple feeding appliances or means for advancing the
carbons during combustion, than exists with the arc lamps at present in general use.
Our improved feeding apparatus consists essentially of a high resistance magnet
circuit in shunt to the main circuit, so arranged that during the consumption of
the carbons the increasing resistance of the are increases the strength of the high
resistance circuit, and such increased strength of the shunt magnets, by attracting
the armature, draws back or compresses a spring until the shunt magnet circuit is
ultimately broken, when the compressed spring is liberated to perform the work of
feeding or advancing the carbons.
In one convenient application of our invention the armature is mounted on a
lever having a pawl at one end which engages the teeth of a ratchet wheel and
actuates a screwed rod supporting the top or positive carbon holder. When the
ratchet is turned or revolved by the pawl the positive carbon holder is advanced
towards the lower or negative carbon, and such action continues until the normal
resistance of the arc is re-established, when the feeding movement is arrested until
further consumption of the carbons.
The high resistance circuit is made complete by a contact which is always
maintained except when the armature is drawn towards the magnet against the
resistance of the regulating spring, when contact is broken to permit of the feeding
operation. The contact may take the form of a piston carried in the pawl lever
hereinbefore described, or instead of a piston we sometimes employ a sliding switch
actuated by such lever.
We preferably dispense with the use of magnets or other appliances for striking
the are in the construction of our improved lamps. We point or sharpen the upper

page_text: or positive carbon, and in trimming the lamp the carbens are not placed in contact.
On the current being admitted it passes by way of the shunt circuit, and causes the
feeding mechanism to be instantly operated, thus advancing the positive carbon
until it is brought into contact with the negative carbon, when the current instantly
passes by the main circuit and consumes the sharp point of the positive carbon and
so forms the arc. The carbons are kept from contact except during the feeding
operation hereinbefore described, and do not rest upon each other as in ordinary
arc lamps.
When employing an are striking arrangement in connection with our lamp
we use a magnet or magnets forming part of the main circuit for attracting
an armature which is preferably connected to a lever arranged to operate the
positive carbon holder by means of a screwed rod, and thus to move the carbon
to a sufficient extent to establish the arc and to maintain the same in such position
during the whole time that current is passing. The feeding is effected entirely by
means of the shunt circuit hereinbefore described.
The screwed rod hereinbefore described of the feeding mechanism eugages or
gears with a segmental nut, the parts or segments being held together by a spring
elip that can be readily opened to release the nut for permitting of its being moved
freely up or down the rod during trimming of the lamp.
In the application of our invention to a double lamp or one arranged to carry two
pairs of carbons in such a manner that the second pair are brought into use after
the first pair is burnt out, we employ a second positive carbon holder working on
or supported by the rod which supports the first holder. The second pair of
carbons are kept out of contact and out of gear with the feeding mechanism until
required by means of a forked lever, and such lever also holds open the nut and
retains the same together with the carbou holder in one fixed position.
When the first pair of carbons are on the point of being burnt out the continued
advance of the positive carbon holder carries forward a sleeve connected by a rud
with the forked lever, and the movement of such lever puts the split nut of the
second positive carbon holder into gear with the feeding mechanism, and the
second positive carhon is thus automatically brought into use.
In the three accompanying sheets of explanatory drawings to be hereinafter
referred to.
Figure A on Shuet 1 is a front elevation, and Figure B a side elevation of a
double are lamp constructed and arranged in accordance with our invention.
On Sheet 2, Figure C is a sectional plan of the lamp through the line ab
Figure B;
Figure D is an elevation and Figure E a plan representing an alternative.
arrangement of the contact breaker.
Figure F on Sheet 3 is a sectional plan through the line ed Figure A, and
Figure G a similar view through the line ef Figure A.
The same reference figures in the different views indicate the same parts.
The lamp comprises à main frame 1 carrying main magnets 2 for striking the
are, and the shunt magnets 3 for the feeding mechanism. The columns 4 and 5
(insulated from the main frame by means of the fibre washers 10) support the
wooden bridge 6 and the metal top cover 7, the whole being secured together by
the terminals 8 and 9.
On a projection of the soft iron core 11 of the lower main magnet we mount the
armature 12 and to such armature we fasten one end of the bell crank lever 13,
into the opposite end of which is fitted the pin 14 of the sliding or movable bush 15,
contained in the projecting boss 15. The feed screw 16 is passed through such
sliding bush, and to the top end of the screw we attach the ratchet wheel 17.
The pin 18 is the hinge or pivot pin of the feeding or operating lever 19 having
the ratchet pawl 20 pivotted to one end, such pawl being held up to the ratchet
wheel 17 hy means of the spring 21. To the other end of the feeding lever 19 we
connect the regulating screw 22 which is provided with a spring 23. The
armature 12 is also secured to the lever 19, adjacent to the shunt magnets.

page_text: The contact breaker consists of a platinum tipped plunger 24 pressed out by a
spiral spring 25 both plunger and spring being carried in a pocket formed on the
lever 19. The bracket 26 for carrying the contact screw is fixed on the main
frame by the two screws 27 insulated by the fibre pad 28. The platinum tipped
contact screw 29 which is set by means of the thickness washer 30 completes the
circuit by the lever 19.
The metal tubes 31 and 32 secured to the main frame 1 carry the double carbon
holder 33 which is insulated by the fibre washers 34. The two negative carbons
are secured in the apertures 35 by the screws 36. The positive carbon holder 37,
which is the first to feed down, is free to slide along the tubes 31 and 32 and is
moved by means of the feed screw 16 working through the split nut 38 which is
closed on to the screw by the spring 39. The second positive carbon holder 40
is also free to slide on the tubes 31 and 32, and is also moved by the screw 16
working through the split nut 384. The nut 384 is hell open or off the screw 16
by the claw-like lever 41, which, being pivotted on the bracket 42, can slip off the
inclined surfaces of the split nut 384 and thus put the positive carbon holder 40
into gear as soon as the end 43 of the first positive carbon holder sufficiently
depresses the slider 44 to operate the lever 41 through the medium of the rod 45.
When the split nut 38 is thus released from the lever, it is closed on the screw 16
by the action of the spring 46.
The alternative arrangement of contact breaker shown at Figures D and En
Sheet 2, consists in the provision of the lever 19 with a pin 19 which works in the
slotted end of the spring arm 47, such arm being pivotted on the bracket 43 which
is fixed on the main frame 1, the spring arm making the contact by sliding on the
surface of the insulated bracket 49, also fixed on the main frame.
The action of the lamp is as follows.-The current on entering by the positive
terminal passes through the main magnets 2 to the positive carbou and thence
through the are to the negative carbon and to the negative terminal. The current
in passing through the main magnet magnetises them and by attracting the
armature 12 lifts the screw 16 (through the medium of the lever 13 and sliding
bush 15) thereby raising the positive carbon holder and striking the are.
The increasing resistance of the are during the consumption of the carbons
producing a correspondingly increased resistance iu the main circuit, more current
is caused to pass through the shunt coils 2, whereby the pull of the regulating
spring 23 of the operating lever 19 is overcome, and the lever and its armature is
drawn towards the magnets till the contact at 29 is broken.
causes the pawl 20 to move the ratchet wheel 17 in order to bring the carbons
The spring 23 then
nearer together. This action takes place as often as is required to bring the are
to its normal resistance.
The second pair of carbons are brought into operation after the first pair are
consumed as far as is practicable by the operation of the slider 44 which is
gradually depressed as the end 43 of the first positive carbon holder presses upon
its upper end. The movement of the slider being transmitted through the rod 45,
causes the claw-like lever 41 to release its hold of the split nut on the carbon
holder 40, permitting the nut to engage with the screw 16 and thus to bring the
second pair of carbons into action as soon as the resistance of the are between the
first pair increases sufficiently to cause the feeding mechanism to work.
The alternative feeding arrangement comprising the contact breaker shown at
Figures D and E is identical in its action with the arrangement herein before
described, with the exception that the contact is a sliding one coutinually cleaning
its point of contact and thus requiring no platinum.
Having now particularly described and ascertained the nature of our said iuven-
tion, and in what manner the same is to be performed, we declare that what
we claim is.
1. The improved method of advancing electric are lamp carbons comprising
the use of main and shunt magnet circuits so arranged that with the consumption

page_text: of the carbons the increasing resistance of the arc will cause an increase in the
strength of the shunt circuit whereby the feeding mechanism is set in operation,
substantially as described.
2. In electric arc lamps, the combination of main and shunt magnet circuits
with a lever pivotted to the lamp frame and provided with a spring connection,
an armature, a ratchet wheel, operating pawl, and a contact breaker, substantially
as and for the purposes described and as illustrated.
3. In electric lamps the improved method of striking the arc without the use of
magnets or other ordinary are striking appliances, substantially as described.
4. An arc striking appliance for electric arc lamps comprising an armature
arranged for attraction by a magnet forming part of the main circuit and so
connected with a lever and the positive carbon holder that the carbon is
sufficiently raised to effect the striking of the arc, substantially as described and
as illustrated.
5. In carbon feeding appliances for electric arc lamps the combination with
an operating spring lever actuated against its spring by the influence of a high
resistance circuit, of a feed screw and segmental or disengaging nut in connection
with the positive carbon holders, substantially as described and as illustrated.
6. In double arc electric lamps the means whereby the second pair of carbons
are automatically brought into use when the first pair is burnt out, substantially
as described and as illustrated.
7. A double arc electric lamp constructed and arranged substantially as described
and as illustrated.
8. The improved general construction and arrangement of parts forming the
improvements in electric arc lamps substantially as and for the purposes described.
MARKS & CLERK,
18 Southampton Buildings, London, W.C., and
13 Temple Street, Birmingham, Agents for the Applicants.