Improvements in Electric Are Lamps.
Year: 1897

page_text: Date of Application, 26th Feb., 1897
Complete Specification Left, 24th Dec., 1897-Accepted, 29th Jan., 1898
Improvements in Electric Are Lamps.
I, RALPH GAYNOR, of 2, New Maughan Street, New Benwell, Newcastle-on-Tyne,
in the County of Northumberland, Engineer, do hereby declare the nature of this
invention to be as follows:-
My invention relates to electric are lamps and is chiefly designed to improve the
construction thereof and to prevent fluctuations or irregularities in the light emitted
thereby.
One feature of my said invention consists in mounting one or both of the moveable
carbon holders on the bend of a U-shaped tube which slides freely in or over parallel
tubular guides attached to the body of the lamp, and in providing for the feeding of
the carbon or carbons by means of a cord, chain or the like extending through each
U-shaped tube and its tubular guides.
Another feature of my said invention is the provision which I make, in feed or
regulating mechanisms in which a brake-wheel and brake-block or clutch is employed,
for effectually preventing any excessive motion of the brake-wheel after it has been
released from the pressure of the brake-block or clutch and for gradually bringing the
brake-wheel and brake-block into contact with each other and increasing the friction
between them until the feeding of the carbon or carbons is arrested.
For this purpose I so arrange the said brake-wheel that, as it rotates, it will also
move bodily sidewise and thus follow up the brake-block or clutch through a short
distance, when such brake-block or clutch is brought out of engagement with it by
the action of the regulating solenoid or solenoids of the lamp. Or I can arrange for
the said brake-block or clutch to be moved sidewise in a similar manner. The said
brake-block or clutch is moreover adapted to turn the brake-wheel in the opposite
direction to that above mentioned in order to part the carbons in forming or striking
the arc.
"
"
In constructing a lamp according to my said invention I preferably make the guides
for the U-tube in the form of tubes open at both ends and I stay their extremities
by means of a ring or semi-circular tie-piece. I provide for controlling the motion
of the aforesaid U-shaped tube by means of a flexible cord, chain, tape or the like
which is passed through the tubular guides and through the U-tube. This cord, tape,
chain or the like, which may also serve as a conductor, is either fixed at one end and
connected to the drum or the like of the feed-mechanism at the other end, or is
attached to drums or the like in connection with the feed-mechanism at both ends,
so that by increasing or diminishing the length of the cord, tape, chain or the like
by means of the said feed-mechanisin, the carbon-holder is moved in one or the other
direction to "strike" or to regulate the length of the arc. In this manner the resultant
pull or lift of the cord, tape, or the like always acts centrally or in a direction parallel
to the guiding surfaces.
In practice I generally prefer to employ the arrangement in which the cord, chain
or the like is fixed at one end and moved at the other since the friction or retarding
force produced by the flexible cord riding over the bend of the U-tube has a regulating
action in connection with the clutch gear employed.

page_text: By employing the arrangement above mentioned I am enabled to effectually
prevent any violent motions of the movable carbon or carbons without increasing their
weight or employing dash-pots or the like. It is obvious that this part of my
invention with slight modifications is applicable to any type of arc lamp.
In my improved feed-mechanism I mount the brake-wheel on a spindle which is
provided with a screw-thread engaging with a fixed nut which may, if desired, form
one of the bearings of the said spindle. The said screw-thread may have any suitable
pitch so as to obtain a gradual and regular feed and it is so arranged that it will move
the brake-wheel towards the brake-block or clutch when it is turned by the gearing
connecting it to the movable carbon-holder or holders; and I preferably make the
surfaces of the brake-wheel and of the brake-block or clutch conical, and of similar
pitch, so as to permit relative motion whilst ensuring that the said surfaces shall
always, come accurately into contact with one another. Or I can mount the said
brake-block or clutch on a swinging link or otherwise arrange it so as to permit the
relative motion of the parts as above mentioned. In other cases I may arrange for
the screw on the brake-wheel spindle to draw the clutch up against the periphery or
rim of the brake wheel in which case the clutch will have the lateral movement instead
of the brake-wheel.
The gearing for driving or rotating the brake-wheel is obviously of such a nature
as to permit the sidewise or axial motion of its arbor, for example, in the case of tooth-
gearing, one of the gear-wheels is made of sufficient width to remain in engagement
with the other throughout the entire travel of the relatively moving part.
It is obvious that the details of construction of my improved apparatus can be
somewhat further modified without departing from the nature of my said invention.
Dated this 26th day of February 1897.
D. YOUNG & Co.,
11 and 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.
I, RALPH GAYNOR, of 2, New Maughan Street, New Benwell; Newcastle-on-Tyne,
in the County of Northumberland, 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:-
My invention relates to electric arc lamps and is chiefly designed to simplify and
improve the construction thereof and to prevent fluctuations or irregularities in
the light emitted thereby.
One feature of my said invention consists in mounting one or both of the
inovable carbon-holders on the upper or under side of the bend of a U-shaped
tube or tubes preferably arranged to slide freely in or over parallel tubular
guides attached to the body or frame of the lamp, and in providing for
the feeding of the carbon or carbons by means of a cord, chain or the
like extending through the U-shaped tube and its tubular guides. This
cord or its equivalent, which may also serve as a conductor, is either fixed at
one end to the lamp-frame and connected at the other end to a drum or like
part of the feed-mechanism, or it is attached at both ends to drums or like parts
of the feed-mechanism, so that, by winding up or unwinding the said cord, by means
of the said feed-mechanism, the carbon-holder will be moved in one or the other
direction to "strike" or to regulate the length of the arc. With this arrangement, the
resultant pull or lift of the said cord will always act centrally or in a direction
parallel to the guiding surfaces.

page_text: In practice I prefer to employ the arrangement in which the core, chain or the
like is fixed at one end and wound up or unwound at the other, since the friction or
retarding force produced by the flexible cord riding under the bend of the U-tube
has a regulating action in connection with the clutch-gear or brake-gear employed.
And violent motions of the movable carbon or carbons are thereby effectually,
prevented without the use of heavy iron cores or the employment of dash-pots or the
like. It is obvious that this part of my invention with slight modifications is
applicable to any type of arc lamp.
a
Another feature of my said invention is the provision which I make, in lamps
provided with feed- or regulating mechanism in which a brake-wheel and
brake-block or clutch are employed, for effectually preventing any excessive motion
of the brake-wheel after it has been released from the pressure of the brake-block or
clutch. To attain this result I so construct and arrange the parts that, during the
feeding of the carbons, the brake-wheel and brake-block will be gradually and
automatically caused to approach each other or brought into contact with each other
and the friction between them increased until the feeding of the carbon or carbons
is arrested.
For this purpose I sometimes so arrange the said brake-wheel that, as it rotates,
it will also move bodily sidewise and thus follow up the brake-block or clutch
through a short distance, after such brake-block or clutch has been withdrawn from
it by the action of the regulating solenoid or solenoids of the lamp. Or I arrange
for the said brake-block or clutch to be moved sidewise in a similar manner. The
said brake-block or clutch is, in some instances, adapted to turn the brake wheel in the
opposite direction to that above mentioned in order to part the carbons in forming
or striking" the arc.
My said invention, moreover, comprises other improvements hereinafter set
forth.
In the accompanying drawings I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a front elevation, partly in vertical section showing one form of my
improved arc lamp.
Figure 2 is a partial vertical section on the line x-x, Figure 1.
Figure 3 is a plan, the top of the frame being removed.
Figure 4 is a partial vertical section, and
Figure 5 a horizontal section through the centre of the brake-wheel, illustrating
another form or modification of my invention.
Figures 6 and 7 are similar views to Figures 4 and 5, respectively, showing
another modification of my said invention.
Figures 8 and 9 are similar views showing a further modification of my said
invention.
Figure 10 is a partial vertical section of a rack-and-pinion lamp showing the
application of my invention thereto.
Figure 11 is a front elevation,
Figure 12 a side elevation and
Figure 13 a plan, the cap or cover being removed, showing another modification
of my improved rack-and-pinion lamp.
Figure 14 is a front elevation, partly in vertical central section,
Figure 15 a vertical section through the axis of the brake-wheel, and
Figure 16 a plan, the cap or cover being removed, showing a still further
modification of my invention.
A is the lamp-frame; B, B are vertical tubular guides fixed therein; C, C¹ are
the upper and lower carbons; D is the U-shaped tube which supports the lower
carbon C. This tube is provided at its extremities with rings D¹ of ebonite or other
suitable insulating material, and is fitted to slide up and down in the tubular
guides B, which are provided at their lower ends with bushes B¹ of ebonite or like
inaterial so that the tube D is insulated from the frame A.
In Figures 1, 2 and 3, main and shunt solenoids M, S are employed, the movable

page_text: cores c¹, c² of which are pivotally connected to a rocking cradle or lever L, which
is pivoted approximately in the centre of the lamp, as at L. On the underside of
the said lever L near its pivot L', are cut angular notches or brake-surfaces N
corresponding to the angle or bevel of the rim of the brake-wheel W, so that the
said surfaces shall always come accurately into contact with one another
notwithstanding the relative motion of these parts, as hereinafter described. The
said brake-wheel is mounted upon a screw-threaded spindle or axle a which is fixed
by means of a collar a¹ on a vertical tube T which is movable up and down in top
and bottom guides in the frame A, through a distance sufficient to strike the are.
The upper carbon C is fixed in a holder or rod R which is guided by and is free to
move up and down in the tube T; to this rod R is attached one end of a cord b which
is passed over a pulley p and has its other end attached to a drum W¹ formed or fixed
on the brake-wheel W, a suitable weight E being provided upon the said rod R for
the purpose of feeding the carbons as hereinafter described. To a pin H¹, insulated
from the frame A and connected through the main coil M to the negative terminal I
of the lamp, is attached a flexible cord, chain or ribbon H which is preferably made
of conducting material and which is passed through the tubular guides B and
through the U-shaped tube D from end to end thereof and, after passing over a guide-
pulley, is attached to a drum W2 on the brake-wheel. Or, if this drum be made
of larger diameter, the said guide-pulley may be dispensed with and the cord or
ribbon H passed directly around the drum.
On starting the lamp, the main or series coil M receives the full current and pulls
down its core c², thus turning the cradle or lever L, which presses down the brake-
wheel W and tube T, thereby simultaneously lowering the lower carbon C¹ and
raising the rod R and with it the upper carbon C, and striking the arc.
The current enters the lamp at the positive terininal F and passes through the
frame A to the positive carbon C and thence, via the are, the negative carbon C¹,
the tube D and cord H to the pin H¹ whence it passes through the main coil M to
the negative terminal F¹, the part of the cord H in contact with the pulley p¹ and
drum W2, being made of insulating material or being otherwise suitably insulated
from the frame of the lamp.
When the current in the shunt solenoid S predominates, the lever L is turned
about its pivot in the reverse direction, thus withdrawing the clutch-surfaces N from
the brake-wheel W and allowing the latter to rotate so that the carbons will approach
each other. In the rotation of the brake-wheel W, it is gradually moved along its
screw-threaded axle a, and is thus caused to follow up the said clutch surfaces N and
again come in contact therewith. Any undue feed-movement of the carbons is thus
effectually prevented. The main or series coil M also assists in controlling the feed
by pulling the clutch-surfaces N down upon the brake-wheel W.
I preferably make the drums W1, W2 on the brake-wheel, which carry the
conducting cords or ribbons H, b conical as shown in Figure 3, in order to equalise
the pull on the brake-wheel as the carbons are gradually consumed, and the said
brake-wheel travels sideways, thus causing the flexible cords or ribbons H, b to
gradually ride up the cones. Their pull or leverage is thus increased gradually in
proportion to the consumption of the carbons and a fairly constant pull on the brake-
wheel obtained. This action is also assisted by the fact of the brake-wheel travelling
laterally away from the central pivot of the lever L, whereby the relative leverage
of the main coil is decreased in fair proportion to the consumption of the carbons.
As a modification of this arrangement, I sometimes spirally groove the rim of the
brake-wheel and cause a tongue or corresponding grooved brake-block to project down
into same, the operations being similar to that above described in striking the are
and feeding.
In the modification of my improved mechanism shown in Figures 4 and 5, the
"feed" is controlled mainly by means of the shunt-coil S, the main or series coil M
having its core c² attached to an arm e on the tube T and serving for striking the arc.
The end I of the lever L, instead of being connected to the core c², is in this case
attached to a spring & which opposes the pull of the shunt coil S. The tube T is

page_text: provided with guide-arms T¹ riding against the tubes B so as to keep the brake-
wheel W in its proper position. I preferably form the core c² of the main-coil M as
shown, with projecting rings or flanges c³ fitting easily into the tube in the interior of
the coil, thus forming a dash-pot arrangement for preventing violent motion of the
said core.
In the arrangement shown in Figures 6 and 7, provision is made for lifting both
ends of the flexible cord H. For this purpose the ends of the said cord are passed
over guide-pulleys p² and are connected directly to a drum W on the brake-wheel W.
In this case the said brake-wheel is arranged to be raised by an inclined inwardly-
extending brake-tongue or clutch-surface N¹ on the rocking lever L, which is situated
below the said wheel and is pivoted at one side of the centre as at L, Figure 7, the
screw-threaded spindle a being provided with a guide-frame a² and a fork a³ adapted
to slide on the tubes B. The upper carbon-holder is attached to a weight E at the
lower end of a cord 6' the upper end whereof is wound around the drum W' of the
brake-wheel W in the opposite direction to the ends of the cord H.
According to another form or modification of my invention shown in Figures 8
and 9, I pivot a swinging augular brake-block or clutch N¹ at N2 to the rocking
lever Land provide the said block or clutch with a downward extension N³ which
is weighted or provided with a suitable spring so as to press it against the bevelled
periphery of the brake-wheel W. To this block or clutch N₁ is rigidly secured a
curved rack with one or other of the teeth whereof a vertical pawl or arm g is
adapted to engage. This pawl g is pivotally mounted on the frame A and retained
in engagement with the rack f by means of a spring g¹.
The operation of this arrangement is as follows:-Upon the main solenoid M pulling
down the core c², the brake-block or clutch N¹ is raised and, since it is pressed against
the rim of the wheel W by virtue of its weighted extension N³ it turns the said wheel
through a small angle in the direction of the upper arrow, thus striking the arc.
When the arc is struck, the shunt-coil S is energized, and pulls down the core c¹,
and, the pawl g being in engagement with one of the teeth of the curved rack f, the
brake-block or clutch is swung slightly to the left, and the brake-wheel W thus
released. The said wheel then rotates in the direction of the lower arrow, and the
carbons are fed towards one another until the brake-wheel, by virtue of its lateral
motion, again abuts against the block or clutch N' and has its motion checked
thereby. It will be seen that, in this compensating arrangement, the main or series
coil M also aids in controlling the feed, and the solenoid cores c1, c2 will always remain
in approximately the same position relatively to their coils whilst the full advantage
of the above described improvements will be secured.
The method of applying this compensating arrangement may be considerably
varied without departing from the nature of my said invention.
In Figure 10 the brake-wheel W is fitted upon the screw-threaded spindle of a
pinion h geared with a rack; on the upper carbon-holder, the lever L being pivoted
at one end L and adapted to be lifted for striking the arc and lowered for feeding
by a differentially-wound solenoid M¹ the core of which is coupled to the other
end of the said lever, the brake-block or tongue N¹ is, in this case, formed with an
inclined upper surface which will press against the bevelled rim of the brake.
wheel W, in a similar manner to that described with reference to the preceding
figures.
Figures 11, 12 and 13 show another method of applying my invention to a rack
and pinion lamp wherein the brake-wheel W and pinion are mounted in a frame k
which slides up and down on a central tube A2 fixed in the frame A, the pinion h
being of sufficient width to remain in contact with the rack j throughout the lateral.
travel of the brake-wheel W. The lever L is arranged beneath the brake-wheel W,
and is controlled by the two solenoids M and S.
In Figures 14, 15 and 16 I have shown my invention applied to a lamp wherein
a flexible conductor 62 feeding the positive carbon is passed over a guide-pulley p³
and through the base-plate of the lamp-frame and is attached to the sliding weight F

page_text: bearing the positive carbon C. The arrangement of the other parts is somewhat
similar to that described with reference to Figures 1 to 3.
The above described arrangements are applicable to double-carbon lamps or to
lamps of the non-focusing, enclosed, shunt or inverted types.
I sometimes mount the lower carbon-holder on the bend of a U-shaped tube as
above described, and attach the upper carbon-holder to the underside of the bend
of another U-shaped tube, through which is threaded another cord or ribbon for
raising and lowering the upper carbon. In this case, the ends of the last-named cord
or ribbon may be passed around the drum or drums for lifting the cord or ribbon of
the lower U-shaped tube, so that, in the downward movement of the upper carbon,
the lower carbon will be raised.
It is obvious that the details of construction of my improved apparatus can be
somewhat further modified without departing from the nature of my said invention.
And I consider as an equivalent of my U-shaped tube, a U-shaped grooved bar which
will serve for the same purposes with the exception of enclosing the cord or ribbon.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
First. In an electric arc lamp, a U-shaped tube for supporting one of the carbons.
sustained by a flexible cord or the like, which extends through the said tube from
end to end thereof and serves for raising and lowering the said carbon.
Second. An electric arc lamp in which a U-shaped tube for supporting one of the
carbons, is sustained by a flexible cord or the like extending through the said tube,
which cord is attached at one end to a fixed support and at its other end to means
for lifting it, and serves for raising and lowering the said carbon and also as a friction-
brake for preventing violent motions of the said carbon in feeding, substantially as
herein before described and for the purposes specified.
Third. An electric arc lamp wherein a flexible cord or the like is passed through a
U-shaped tube sliding in suitable guides and adapted to support one of the carbons,
and is attached at both ends to a suitable device for raising and lowering the same,
substantially as hereinbefore described and for the purposes specified.
Fourth. In an electric arc lamp, the combination of a U-shaped tube for supporting
the lower carbon, a flexible cord or the like passing through the said U-shaped tube,
and a brake-wheel provided with a drum or drums on which are wound one or both
ends of the said flexible cord or its equivalent, substantially as, and for the purposes,
hereinbefore described.
Fifth. A regulator for an electric are lamp, comprising a brake-wheel and a
brake-block or clutch so constructed and arranged that the rotation of the said
brake-wheel, when released, will cause the gradual re-application of the said
brake-block or clutch by the relative movement of either or both of the parts.
Sixth. In a regulator for an electric arc lamp, a brake-wheel mounted on a
screw-threaded axle in such a manner that, by its rotation during the feeding of the
carbon or carbons, it will have a lateral movement imparted to it relatively to the
brake-block or clutch, substantially as, and for the purposes, hereinbefore described.
Seventh. The modification of my invention in which the upper carbon-holder is
connected with the brake-wheel or drum by means of a rack and pinion, substantially
as described.
Eighth. The combination of the U-shaped tube, the flexible cord or the like
extending through the same and wound upon a drum on the brake-wheel, the
rocking-lever and brake-block or clutch actuated by the main and shunt-coils,
and a compensating device which permits the operation of the said brake-block or
clutch with but a slight change in the position of the said rocking lever, substantially
as, and for the purposes, herein before described.
Ninth. An electric arc lamp provided with my improved regulating-mechanism
constructed substantially as described with reference to either of the forms or

page_text: modifications illustrated in the accompanying drawings, and operating as, and for
the purposes, above specified.
Dated the 24th day of December 1897.
D. YOUNG & Co.,
11 and 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.