Year: 1888

page_text: Date of Application, 20th June, 1888
Complete Specification Left, 18th Apr., 1889
Complete Specification Accepted, 18th May, 1889
We, WALTER RUSSELL MORTIMER of No. 11 Alexandra Square South Kensington,
Electrician, and JAMES HOLLOWAY of No. 10 Milman Street Bedford Row,
Electrical Engineer do hereby declare the nature of this invention to be as
follows:-
Our invention has for its object the construction of electric arc lamps in an
exceedingly simple and consequently inexpensive manner while maintaining perfect
efficiency of action.
For this purpose we construct the lamp with a single solenoid having by preference
both a main and a shunt coil, within which is a tubular core through which passes a
tube that constitutes the upper carbon holder, the core being made to automatically
grip or release the tubular carbon holder as it is moved up or down by the action of
the solenoid. To effect this, there is pivotted to the lower end of the core a bell-crank
lever, the short arm of which carries à pivotted block, adjustable by a screw, and which
is presented to the side of the tubular carbon holder, while the long arm of the lever
passes through a slot in a tubular casing enclosing these parts and is connected by a
helical spring to a flange on the lower end of the said casing. Thus when the tubular
core is drawn upward by the action of the current passing through the main coil of
the solenoid, it carries the fulcrum of the lever with it, and consequently as the long
arm hereof is held by the spring, the short arm is made to move inwards so as to
ihe block against the tubular carbon holder, and in thus nipping it against a forked
bearing surface on the opposite side of the core, this is made to carry the carbon
holder with its carbon upward with it, so as, by separating the carbons, to form the
arc. When by the burning away of the carbons the arc's resistance increases beyond
the normal and consequently the attraction of the solenoid decreases owing to the
weakened current, the tubular core descends slightly and in so doing causes the grip
of the lever to be slackened sufficiently to allow the tubular holder to slide downward
to a small extent until the normal length of the arc is re-established, whereupon the
attraction of the solenoid is again increased sufficiently to cause the core to grip the
carbon holder.
press

page_text: Owing to the spring connection of the lever, its action in gripping and releasing the
carbon holder is made to take place very gradually, and without jerk, so that the
operation of the apparatus is such as to effect practically a continuous slow downward
feed of the carbon in proportion as it is consumed, and this action is capable of being
regulated with great nicety by means of the before mentioned adjusting screw, which
adjusts the tension of the spring at which a gripping of the carbon holder takes
place.
It is found that, the apparatus is rendered so sensitive by these means, that a very
steady feed of the carbons can be effected even without the use of a shunt coil in the
solenoid.
The upper carbon, which passes down through the tubular holder, is held at its
lower end by the following device. On the lower end of the tube is formed a flanged
socket, in which fits a ball with a downward directed cylindrical neck through which
the carbon passes. Slits extend along the greater part of the ball and its neck, so as
to afford them a spring action, and over the neck is placed an annular disc, one point
of which is connected by a slot to a stud on the flange of the socket, while on the
opposite side it carries a screw that screws into the said flange, so that on screwing
this up,
the disc is made to compress the ball and neck and cause it to nip the carbon.
As the ball is capable of having its position shifted to a certain extent in the socket
and disc, it can be adjusted so as to insure that the upper carbon shall be accurately in
line with the lower carbon.
The above described improvements are applicable to arc lamps either of the kind
with stationary lower carbon holder, or of the kind with moveable lower carbon holder,
for maintaining a constant focus.
When employing a lamp of the latter kind, I arrange the lower carbon holder with
lateral slides sliding up and down on guide rods the upper ends of which are fixed with
insulating washers to the before mentioned lower flange on the tubular casing of the
solenoid core apparatus, this casing being also provided with two upper flanges
at some distance apart, in the space between which are wound the solenoid coils.
To the top of the upper flange is fixed a central tubular extension, within which the
upper tubular carbon holder works up and down, and the upper end of which has the
necessary connecting device for the insulated suspension of the lamp.
The upper carbon holder has connected to the flange of its socket one end of a con-
ducting cord or chain which is led up over a pulley on a plate which is fixed in
conducting contact with the underside of the bottom flange of the before described
casing, so that the electric current being led to this casing from the main circuit, it
passes through the cord to the upper carbon holder.
The other end of the cord passes down from the pulley to an insulated attachment
on an arm of the lower carbon holder, so that as the upper carbon holder descends on
the burning away of the carbons, it effects the raising of the lower carbon holder by
means of the said cord. The current passes from the lower carbon holder through the
above mentioned arm to the one guide rod, the upper insulated end of which is con-
nected to the one terminal of the main solenoid coil, the other terminal of which is
connected to an insulated post on the flange of the casing, which post is also connected
to the second lead of the main circuit.
The lower carbon is held in a split screw socket which, in being screwed into the
holder grips the carbon.
It will be evident that the before described construction of spherical clip on the
upper carbon holder is also applicable to the carbon holders of other constructions of
arc lamps.
Dated this 20th day of June 1888.
ABEL & IMRAY,
Agents for the Applicants.

page_text: We, WALTER RUSSELL MORTIMER, of No. 11 Alexandra Square, South Kensington
Electrician, and JAMES HOLLOWAY, of No. 10 Milman Street, Bedford Row, Electrical
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 :-
Our invention has for its object the construction of electric arc lamps in an
exceedingly simple and consequently inexpensive manner while maintaining perfect
efficiency of action.
For this purpose we construct the lamp with a single solenoid having by preference
both a main and a shunt coil, within which is a tubular core through which passes a
tube that constitutes the upper carbon holder, the core being made to automatically
grip or release the tubular carbon holder as it is moved up or down by the action of
the solenoid.
To effect this, there is pivotted to the lower end of the core a bell-crank lever, the
short arm of which carries a pivotted block adjustable by a screw, and which is
presented to the side of the tubular carbon holder, while the long arm of the lever
passes through a slot in a tubular casing enclosing these parts and is connected by a
helical spring to a flange on the lower end of the said casing. Thus when the tubular
core is drawn upward by the action of the current passing through the main coil of
the solenoid, it carries the fulcrum of the lever with it, and consequently as the long
arm hereof is held by the spring, the short arm is made to move inwards so as to
press the block against the tubular carbon holder, and in thus nipping it against a
forked bearing surface on the opposite side of the core, this is made to carry the carbon
holder with its carbon upward with it, so as, by separating the carbons, to form the
are. When by the burning away of the carbons the arc's resistance increases beyond
the normal and consequently the attraction of the solenoid decreases owing to the
weakened current, the tubular core descends slightly, and in so doing causes the grip
of the lever to be slackened sufficiently to allow the tubular holder to slide downward
to a small extent until the normal length of the arc is re-established, whereupon the
attraction of the solenoid is again increased sufficiently to cause the core to grip the
carbon holder.
t
Owing to the spring connection of the lever, its action in gripping and releasing
the carbon holder is made to take place very gradually, and without jerk, so that
the operation of the apparatus is such as to effect practically a continuous slow
downward feed of the carbon in proportion as it is consumed, and this action is
capable of being regulated with great nicety by means of the before mentioned
adjusting screw,
which adjusts the tension of the spring at which a gripping of the
carbon holder takes place.
It is found that the apparatus is rendered so sensitive by these means, that a very
steady feed of the carbons can be effected even without the use of a shunt coil in the
solenoid.
The upper carbon, which passes down through the tubular holder; is held at its
lower end by the following device. On the lower end of the tube is formed a flanged
socket, in which fits a ball with a downward directed cylindrical neck through which
the carbon passes. Slits extend along the greater part of the ball and its neck, so as

page_text: to afford them a spring action, and over the neck is placed an annular disc, one point
of which is connected by a slot to a stud on the flange of the socket, while on the
opposite side it carries a screw that screws into the said flange, so that on screwing
this up, the disc is made to compress the ball and neck and cause it to nip the carbon.
As the ball is capable of having its position shifted to a certain extent in the socket
and disc, it can be adjusted so as to insure that the upper carbon shall be accurately
in line with the lower carbon.
The above described improvements are applicable to arc lamps either of the kind
with stationary lower carbon holder, or of the kind with moveable lower carbon holder,
for maintaining a constant focus.
When employing a lamp of the latter kind, I arrange the lower carbon holder
with lateral slides sliding up and down on guide-rods the upper ends of which are
fixed with insulating washers to the before mentioned flange on the tubular casing
of the solenoid core apparatus, this casing being also provided with two upper
flanges at some distance apart, in the space between which are wound the solenoid
coils.
To the top of the upper flange is fixed a central tubular extension, within which the
upper tubular carbon holder works up and down, and the upper end of which has the
necessary connecting device for the insulated suspension of the lamp.
The upper carbon holder has connected to the flange of its socket one end of a
conducting cord or chain which is led up over a pulley on a plate which is fixed in
conducting contact with the underside of the bottom flange of the before described
casing, so that the electric current being led to this casing from the main circuit, it
passes through the cord to the upper carbon holder.
The other end of the cord passes down from the pulley to an insulated attachment
on an arm of the lower carbon holder, so that as the upper carbon holder descends on
the burning away of the carbons, it effects the raising of the lower carbon holder by
means of the said cord. The current passes from the lower carbon holder through
the above mentioned arm to the one guide rod, the upper insulated end of
which is connected to the one terminal of the main solenoid coil, the other terminal
of which is connected to an insulated post on the flange of the casing, which post is
also connected to the second lead of the main circuit.
The lower carbon is held in a split screw socket which, in being screwed into the
holder grips the carbon.
It will be evident that the before described construction of spherical clip on the
upper carbon holder is also applicable to the carbon holders of other constructions of
arc lamps.
Figures 1 to 6 of the accompanying drawings shew an arc lamp constructed
according to our invention. Figure 1 shews an elevation of the entire lamp.
Figure 2 shews an elevation of the regulating mechanism. Figure 3 a vertical
section. Figure an enlarged section of the tubular core and clamping device.
Figure 5 an underside view of the latter and Figure 6 a section of the spherical
clip.
A. is the tubular core sliding vertically within the solenoid B; which may either
consist of a single coil in the lamp circuit or of two coils, one being in a shunt circuit,
as is well understood.
Within the core A. is the tubular carbon holder C, having at its lower end the
spherical clip D for holding the upper carbon; this consists of a disc a fixed to the
holder C, a second disc b secured to a by screws c c¹ and a split socket d with
spherical outer surface fitting spherical hollows in the plates a and b.
introducing a carbon into the socket d, this can first be adjusted accurately in
position in the discs, and by then screwing up the screw c¹ it is made to grip the
carbon.
Thus on
To the core A. is pivotted a lever E to which is hinged a block E' acted upon by a
screw F screwing through a lug on the lever; the outer end of the latter is connected
by a spring G to an adjustable eye H carried by the casing I. On the opposite side
of the tubular core is fixed a fork-shaped abutment piece J.

page_text: From this arrangement it will be seen that when, on the passage of a current
through the solenoid, the core A is raised, the lever E being held by the spring G
will cause the disc E to be pressed against the carbon holder C, thereby nipping it
against the piece J, so that the carbon holder will be raised with the core, separating
the carbons and forming the arc. When by the burning away of the carbons, the
resistance of the arc increases, thereby diminishing the current in the lamp solenoid
(and increasing that in the shunt solenoid if this be used) the core A will descend
slightly and the lever E being thus made to loosen its grip on the carbon holder, the
latter will descend by gravity through the core so as to bring the carbons to their
normal distance. The current in the lamp-solenoid being thus increased again, the
core A will be again raised slightly, causing the lever E to again grip the carbon
holder C. By adjusting the disc E¹ by the screw F and the spring G by the screwed
connection H, the position in which the core grips and releases the carbon holder can
be accurately regulated.
In the construction of lamp shewn, both the upper and the lower carbons are moveable
for maintaining a constant focus, the lower carbon holder being carried by a cross-bar K
sliding with sockets K' on rods L insulated from the lamp casing I and connected
by an insulated attachment at K² to a conducting cord or chain M that passes
over a pulley N carried by the casing I, and is connected to the clip D of the upper
carbon.
The one lead of the circuit being connected to the lamp casing, the current passes
thence through pulley N. and chain M. to the upper carbon, and from the
lower carbon through K to one of the rods L which is connected to one end
of the lamp-solenoid, the other end of which is connected to the other lead of the
lamp circuit.
The upper end of the upper carbon is enclosed in a tubular extension of the
frame I. which also serves as suspension for the lamp.
Having now particularly described and ascertained the nature of our said Inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In combination with the tubular core and solenoid of an arc lamp, a lever
pivotted to the core and having at one end a device for clamping the carbon holder
passing through the core, while at the other end the lever is connected to an
adjustable spring, so that when the core is raised by the action of the solenoid when
excited by a current of a certain strength, the lever is caused by the spring to clamp
the carbon holder and thereby raise it with the core, while when the core descends in
consequence of the weakening of the solenoid current, the lever releases the carbon
holder so as to allow it to descend, substantially as herein described.
2. In combination with the carbon holder of a lamp, a clamping device for the
carbon consisting of two discs connected by screws and carrying between them a split
socket for containing the carbon, such sockets having a spherical outer surface fitting
spherical recesses in the discs, so that the socket can be both adjusted in position in
the discs and be made by these to grip the carbon substantially as herein described.
3. In an electric arc lamp, the combination of a solenoid or solenoids B, tubular
core A. with clamping device E. E¹ G J. and upper carbon holder C with spherical
clamping device D for the carbon, arranged and operating substantially as herein
described.
Dated this 18th day of Anril 1889