Improvements in Electric Arc Lamps.
Year: 1899

page_text: Improvements in Electric Arc Lamps.
I, ALFRED GEORGE STOCKWELL, of 46, Delafield Road, Old Charlton, in the
County of Kent, Electrician, do hereby declare the nature of this invention
to be as follows:
My invention has for its object to provide an electric arc lamp, which is simple
and cheap in construction, not liable to readily get out of order, and both light
and strong.
According to my invention, to a plate, or disc, I secure the upper and lower
parts of the lamp. On the underside of the said plate, or disc, are bosses into
which I securely fix side tubes, or rods, to the lower ends of which is secured a
cross-bar provided with extensions through which pass the rods to which the
globe carrier is attached, the tops of these rods having forks, or guides, to slide
on the aforesaid side tubes, or rods, in raising, or lowering, the globe. In
the said cross-bar is a socket into which a plug on the globe carrier enters and
in which it is secured by a pin and bayonet slot, or other fastening, a spring hold-
ing it in position. On the upper side of the said cross-bar is fixed the holder for
the lower carbon insulated from the frame-work, and connected to the negative
lead, which may be done by means of an insulated wire passed down one of the
side tubes, or rods, from the body of the lamp.
Un the top side of the aforesaid plate, or disc, I fix a table preferably rectan-
gular, and with its greater length at right angles to the line in which the side
tubes, or rods, beneath are situated, and upon this table the coils are mounted,
a hole being formed through the centre of the table and the centre of the plate,
or disc, beneath to form guides for the rod which carries the upper carbon holder.
On the top of the coils is a cross-piece, with projections entering the openings in
the upper ends of the coils, to keep the, said coils in position; and projecting
from this cross-piece, and preferably at right angles thereto, are extensions for
carrying the terminals and also for bolts which extend also through corresponding
lugs on the table and clamp the whole together. The centre of the said cross-
piece can carry a screw to which is attached the shackle by which the lamp is
suspended, and the whole of the parts, above the said plate, or disc, can be en-
closed by a casing through which the said screw for the shackle and screws for
the nuts for the attachment of the leads can extend. Between the underside of
the aforesaid table and the plate, or disc, is the brake mechanism which is of
the clutch type, I prefer to employ a brake arranged as follows:-A lever is
centered to downward projections from the aforesaid table, and the respective
ends of this lever are pivotted to the main and shunt cores and dashpot. The
clutch is suspended by a link fitted to this rocking bar at the lifting end, and
at the tripping end by a link or suspended stop, attached to the underside of
the table or by an equivalent stopping device.
The clutch consists of two bars connected together at the ends so as to leave
a space between them for the passage of the rod of the upper carbon holder,

page_text: .
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and centered to these bars are two blocks one on each side of the said rod and
preferably hollowed to fit against it. These blocks are so centered to their
respective bars that when one end of the bars is lifted the clutch tightens on the
said rod, and when the other end is held up whilst the first named end descends
the clutch loosens its hold on the said rod. When therefore the lamp is put in
circuit and the main coil pulls up its core raising the end of the lever to which
it is attached, the clutch, being free from the link or stop, and its one end being
drawn up, the aforesaid blocks firmly grip the rod of the upper carbon holder so
that the carbon is drawn up to strike the are; and as the carbons are consumed
and the resistance is increased, the shunt coil attracts its core which, being con-
nected to the other end of the lever, gives, it a return motion, and in its descent
one end of the clutch is arrested by the link of stop and as the other end descends
the aforesaid blocks release their. hold on the upper carbon rod and the carbon
is fed, and this action is repeated until the carbons are burnt out or the lamp
extinguished. I have presumed, in the foregoing description, that the lamp has
a' fixed lower carbon holder, but it may if desired have a moveable lower carbon
holder and the system be duplicated.
411
1000
JOHNSONS & WILLCOX;
47, Lincoln's Inn Fields, London, W.C., Agents.
-
I, ALFRED GEORGE STOCKWELL, of 46, Delafield Road, Old Charlton, in the
County of Kent, Electrician, 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 has for its object. to provide an electric arc lamp which is simple
and cheap in construction, not liable to readily get out of order, and is both
light and strong, I will describe my invention with reference to the accom-
panying drawings of which Figures 1 and 2 are elevations at right angles to each
other of an arc lamp constructed according to my invention. Figure 3, is a plan
of the lamp with the upper part removed and Figures 4 and 5 represent in plan
and elevation respectively brake mechanism for the upper carbon holder and
Figure 6 illustrates a modification. A is a plate or disc to which are secured
the upper and lower parts of the lamp. On the underside of the said plate or
disc, are bosses B into which are securely fixed tubes or rods C. To the lower
ends of these tubes or rods is secured a bar D) provided with extensions & through
which pass rods e to which the globe carrier e is attached. The upper ends of
the rods c have forks or guides E to slide on the aforesaid side tubes or rods C
when raising or lowering the globe. The cross-bar D is provided with a socket F
to receive a plug G on the globe carrier, which carrier may be secured therein
by a pin and bayonet slot, as shewn, or other suitable fastening, and a spring
may be provided for holding it in position. On the upper side of the bar I is
fixed the holder H for the lower carbon, the said holder being insulated from
the frame-work and connected to the negative lead by means of an insulated
wire passed down, or through, one of the rods, or tubes, C. On the top side
of the plate or disc A is fixed a table I preferably of rectangular form and with
its greater length in a plane at right angles to the plane in which the side tubes;
or rods C are situated. Upon this table the coils W and V are mounted and a
hole is formed through the table and through the plate or disc A to form guides

page_text: for the rod J which carries the upper carbon holder J. On the top of the
coils WV is a bridge piece K, having projections on its underside which enter
openings in the upper ends of the coils to keep the said coils in position; and
projecting from this bridge piece, preferably at right angles thereto, are exten-
sions L, for carrying the terminals, and also bolts or rods M for securing the
coils to the table I which rods extend through lugs m on the said table, and
are secured by nuts m¹. The bridge piece K is provided with a. shackle N by
which the lamp can be suspended and the whole of the parts above, the plate or
disc A can be enclosed by a casing through which the shackle N and terminals /
can extend. Between the underside of the top of the table I and the plate or
disc A, brake mechanism is provided which is of the clutch type and is prefer-
ably arranged as follows. Levers are centered to lugs projecting from the
table I and the ends of these levers are respectively connected to the
cores P P of the main and shunt coils V and W, the core P, or an extension
thereof, entering a dash pot Q on the top of the coil V. The clutch brake is
suspended at one end from the underside of the top of the table I by a rod or
link S and stop S₁ and at the other end by a link R from the ends of the levers 0.
The clutch brake consists of two bars T connected together at their ends so as
to leave a space between them for the passage of the rod J of the upper carbon
holder, and centered to these bars on each side of the said rod are two blocks U,
preferably hollowed to fit against the rod. These blocks are centered at t to the
bars T so that when the bars T are lifted at one end, the blocks U are forced
against the rod J and when the said ends of the bars T descend whilst their other
ends are held up, the blocks release the said rod J and allow it to descend. When
therefore the lamp is put in circuit and the main coil V pulls up its core P,
it raises the ends of the levers O to which the bars T are attached causing the
blocks U to firmly grip the rod J of the upper carbon holder J¹ so that the carbon
is drawn up to strike the arc.
As the carbons are consumed and the resistance
is increased, the shunt coil W attracts its core P which being connected to the
ends of the levers O imparts a return motion to the bars T the descent thereof
at one end being arrested by the stop. S¹ on link S whilst the other ends of the
levers descend and release the hold of the blocks U from the rod J of the upper
carbon holder and so leaves the carbon free to descend. This action is repeated
until the carbons are burnt out, or the lamp extinguished. I have presumed in
the foregoing description, that the lamp has a fixed lower carbon holder, but it
may, if desired, have a movable lower carbon holder connected to the upper
carbon holder by a cord a passing round a pulley y as shewn in Figure 6 so that
both carbons will move together.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. In an electric arc lamp, brake mechanism for governing the feed of the upper
carbon, the said mechanism consisting of the combination, with electric coils, of
brake blocks, arranged to engage and release the upper carbon holder, a lever
or levers, to which the brake blocks.are pivoted, and means for operating the
lever, or levers, by the movement of the cores of the electric coils, substantially
as and for the purposes hereinbefore described.
2. In an electric arc lamp, mechanism for feeding the carbon, the said mech-
anism consisting of the combination of blocks for engaging and releasing the
upper carbon holder, plates or bars to which the blocks are pivoted, so that by
angling the plates or bars in one direction, the blocks will be caused to engage
the carbon holder, and when the plates or bars are moved in the opposite direction
the carbon holder will be released, a rod or link on which the plates at one end
are suspended, a pivoted lever, or pivoted levers connected at opposite ends res-
pectively to the cores of the main and shunt coils of the lamp, to which lever or
levers the plates or bars carrying the blocks are connected, so that when the core

page_text: of the main coil is drawn into the coil, the blocks are caused to grip the carbon
holder, and the carbon is moved so as to strike the arc, and when the core of the
shunt coil is drawn in, by increased resistance, tlie carbon is caused to move so
as to restore or maintain the arc substantially as hereinbefore described.
3. The combination and arrangement of parts constituting the improved elec-
tric arc lamp, herein before described and illustrated by the accompanying draw-
ings.
T L 1
71
.
13
1000
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.