AN ELECTRIC LIGHT ARC LAMP
Year: 1884

page_text: I HENRY FRANCIS JOEL, of 44 Lavender Grove, Dalston, London, in. the County
of Middlesex, Electrical Engineer, do hereby declare the nature of my Invention
for AN ELECTRIC LIGHT ARC LAMP," to be as follows:-
pivot
My invention relates to the construction and regulation of an Electric Light Arc
Lamp. I construct an Electric Light Are Lamp with a compound solenoid coil,
having a moveable core made of iron tube, through the centre of the core, the top
carbon holder passes. The special feature of my invention is a mechanical
movement for regulating the rise and fall of the carbon holder and top carbon
under the influence of an electric current. I take a long double link or hinge, and
pivot one end to the underside of the core, the other end of the links
immediately underneath to the bottom of the inside of the case. This binge forins
a knuckle, with its sides at an angle of about 90° one to the other, and the middle
hinge joint projecting outwards. I connect the hinge to the carbon holder by
means of an additional link, one end of which is attached to the lower link of the
hinge, and the other end to a clamping ring which encircles the carbon rod holder.
I provide an adjustable stop for the projecting hinge joint to butt against." When
not in action the iron core is supported by the hinge, and the clamping ring which
is made a little larger in diameter than the carbon rod holder allows that rod free
movement.
°
When an electric current is sent through the lamp, the iron core is sucked up
into the coil, this tends to straighten the hinge, the clamping ring is tilted by its
connecting link, and clamps and lifts the carbon holder, and top carbon, and thus
forins the arc between the two carbons, when the arc increases in length and
resistance, the reversing action of a shunt coil on the solenoid, causes the core to
descend, this carries the connecting link, and clamping ring, and with it the carbon
holder, until the main coil again preponderates and the reverse action takes place.
The play in the ring when tilted, which is adjustable, is the extent of the permanent
feed given to the carbon by this action.
By this peculiar device, I obtain from the comparative coarse movement of the
core, a certain but much reduced movement of the carbon holder, about 1/th, due
partly to the rise of the bottom link upon its centre, and partly to the straightening
of the connecting link.
I can adjust the proportion of the movement between the core and the carbon
holder, by varying the lengths of the links of the hinge. if I use a long link at the

page_text: bottom and a link only half the length at the top, I reduce the movement of the
carbon holder, and vice versa; or I can alter the proportion by altering the angle
made between the two links, or by altering the length and centre of the connecting
link, I can also regulate the action by making the bottom pivots of the links to
slide nearer or further from the centre, I therefore call this action a "differential
mechanical regulator."
If from any cause the carbons are not separated at the adjusted moment,
I arrange that an additional motion be given to the carbon holder by means of a
slot provided in the pivot of the lower link of the hinge, this enables the whole to
be pulled 'bodily upwards. I make the stop before mentioned to serve as an
electrical contact, which when the lamp is not in action short circuits a greater
portion of the shunt coil, and makes a by pass circuit of a special thick wire coil
introduced in the shunt coil.
I may modify the foregoing by attaching a spring to the clamping ring in place
of the connecting link, as the core is sucked up this spring tilts the ring and rises
the carbon holder, a special feature in the use of the spring is that during the first
half of the rise of the core the pressure increases very slightly, but during the end
of the movement the pressure of the spring, increases to a much greater proportion,
due to the straightening of the lower link, this peculiar action of the spring
accomodates itself to the feed of the carbons, as it is required. The use of the
spring in connection with the links gives a sliding movement to the clamping ring,
and when in action its pressure restrains the movement of the carbon holder. For
some lamps I propose to use two such systems of links or "differential mechanical
regulators," one on each side of the carbon holder with two rings crossed X shape
and pivotted together, or I may use two half ring spring clamps in place of the
rings, the sliding movement given by these spring clamps will ensure a very strady
feed.

page_text: I, HENRY FRANCIS JOEL of 44 Lavender Grove, Dalston, London, in the
County of Middlesex, Electrical Engineer, do hereby declare the nature of my
invention for "AN ELECTRIC LIGHT ARC LAMP, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement:―
In the accompanying drawing, I have shewn Fig 1, a sectional elevation of my
complete Arc Lamp. Fig 2 a diagram of the mechanical movements, and Fig 3, is
a diagram of the electrical connections.
I construct an Electric Light Arc Lamp with a compound solenoid coil; M being
the main coil, and S, the shunt coil, and a moveable core C, made of iron tube,
having extension pieces of brass tube c, c, on each end, and guided by rollers D; D.
The position of the iron core in the coils can be adjusted by unscrewing or
screwing the core up or down on the lower brass extension tube c. Through the
centre of the core, the top carbon holder H, passes.
The special feature of my invention is a mechanical movement for regulating the
rise and fall of the carbon holder H, and top carbon P under the influence of an
Electric current. I take a long double link or hinge L, and pivot one end to the
underside of the core, the other end of the links I pivot immediately underneath
to the bottom of the inside. of the case B..
This hinge forms a knuckle, with its sides at an angle one to the other, and the
middle hinge joint projecting outwards. I connect the hinge to the top carbon
holder H, by means of an additional link l, one end of which is attached to the
lower link of the hinge, and the other end to a clamping ring R, which encircles
the carbon rod holder. I provide an adjustable stop A, for the projecting hinge
joint to butt against. When not in action the iron core C, is supported by the
hinge L, resting against the adjustable stop A, and the clamping ring R, which is
made a little larger in diameter than the carbon rod holder H, and is supported
on an adjustable tube T, and in that position it allows the carbon rod free
movement.
When an Electric current is sent through the lamp, the iron core C, is sucked up
into the coil M, this tends to straighten the hinge L, (see dotted lines in diagram
Fig 2.) the clamping ring R, is tilted by its connecting link l, and clamps and lifts.
the carbon holder H, and top carbon P, and thus forms the arc between the two
carbons, P and N, when the arc increases in length and resistance the reversing
action of the shunt coil S, on the solenoid, causes the core C, to descend, this carries
the connecting link 1, and clamping ring R, and with it the carbon holder H, during
its descent the carbons are fed to that extent, until the clamping ring rests upon the
adjustable support T, and frees the carbon, the main coil M, again preponderates,
and the reverse action takes place. I may damp, or retard the downward movement
of the carbon when freed from the clamping ring R, by means of a friction brush,.
or a dash pot or any other such device. I use a special form of round clamping"
ring or annulus, which is preferably of larger diameter, on the side connected to the
link . When the link 1, is pushed up, this ring turns upon itself, and tilts down
on the side away from the link l, when the link l, descends, the reverse tilting
action takes place (see Fig 2). I may assist this tilting action by an additional
spring or connecting piece (shewn at O, Fig 2). I may place rollers on the sides of
this clamping ring to lessen the friction of its tilting. The play in the ring when
tilted, which is adjustable, is the extent of the feed given to the carbon by this

page_text: action. By this peculiar device I obtain from the comparative coarse movement
of the core, a certain but much reduced movement of the carbon holder, due partly
to the rise of the bottom link upon its centre, and partly to the straightening of
the connecting link. I can adjust the proportion of the movement between the
core and the carbon holder, by varying the lengths of the links of the hinge L, if I
use a long link at the bottom, and a link only half the length at the top, I reduce
the movement of the carbon holder, and vice versa; or can alter the proportion
by altering the angle made between the two-links, or by altering the length and
centre of the connecting link.
I can also regulate the action by making the bottom pivots of the links to slide
nearer or further from the centre, I therefore call this action, a differential mechanical
regulator. If from any cause the carbons are not separated at the adjusted moment,
I arrange that an additional motion be given to the carbon holder by means of a
slot b, provided in the pivot of the lower link of the hinge L, this enables the whole
to be pulled bodily upwards. I make the stop A, before mentioned to serve as an
Electrical contact, with the addition of a spring arm a, which when the lamp is not
in action short circuits a greater portion of the shunt coil, and makes a bye pass
circuit E, of a special thick wire coil wound outside the solenoid coils (see Figs 1
& 3).
I may modify the foregoing by attaching a spring to the clamping ring in place
of the connecting link. 1, or I use a spring J, (see Fig 1.) to press upon the con-
necting link l, as the core is sucked up, this spring tilts the ring R, and raises the
carbon holder H, a special feature in the use of the spring is that during the first
half of the rise of the core, the pressure increases very slightly, but during the
end of the movement the pressure of the spring increases to a much greater
proportion, due to the straightening of the lower link, this peculiar action of the
spring accomodates itself to the feed of the carbons, as it is required. The use of
the spring J, in connection with the links L, l, gives a sliding movement to the
clamping ring R, and when in action its pressure restrains the movement of the
carbon holder H. For some lamps, I propose to use two such systems of links
or "differential mechanical regulators," one on each side of the carbon holder with
two rings crossed X shape and pivotted together, (as shewn at Fig 4,) or I may use
two half ring spring clamps in place of the rings (see Fig 5), the sliding movement
given by these spring clamps will ensure a very steady feed, or in place of using
the springs, I may use a weight as shewn in dotted lines Fig 5, or I may connect
the two links by a double spring J, and clamp R, as shewn in dotted lines Fig. 4.
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, The mechanical device consisting of the links L, connecting link l, or alter-
native spring, the clamping ring R, and adjustable stops A and T, for the purpose of
regulating the carbons in an Electric Arc Lamp substantially as shewn and described
in relation to Figs 1, and 2.
2, The alternative mechanical actions substantially as shewn and described in
relation to Figs 4, and 5.
3, The method of forming a bye pass circuit in combination with the regulating
link mechanism, substantially as shewn and described in reference to Figs 1
and 3.
Dated this 5th do f
1001