Improvements in or relating to Arc Lamps.
Year: 1899

page_text: Date of Application, 12th Aug., 1899-Accepted, 16th Sept., 1899
Improvements in or relating to Arc Lamps.
A communication by CHRISTIAN J. TOERRING, of 1035, Ridge Avenue, Phila-
delphia, in the County of Pennsylvania, United States of America, Electrical
Engineer.
I, GEORGE CECIL. DYMOND, M.I.M.E., of the Firm of W. P. Thompson & Co.,
British & Foreign Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank
Street, Manchester, both in the County of Lancaster, 118, New Street, Birming-
ham, in the County of Warwick, and 322, High Holborn, in the County of
Middlesex, Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
The object of this invention is to construct an arc lamp of the type in which
the arc is formed within a small and substantially air tight globe, for the purpose
of increasing the life of the carbons, and the invention consists in the construction
and arrangement of parts which will be hereinafter described and claimed.
In the drawing, Fig. 1 is in part a longitudinal section and in part a side
elevation of the improved lamp.
Fig. 2 is a side elevation of the lamp.
Fig. 3 is a detail showing the arrangement of the upper carbon carrying
device, and
Fig. 4 is a cross sectional plan taken on the line 4 of Fig. 1.
The top plate 19 has attached thereto a porcelain insulator 191, from which
the lamp is supported. Integral with or attached to the top plate 19 is an annular
casting 192.
A casting 6, which is shown as having three legs, is secured to
the annulus 192 by means of screws as seen in Fig. 2. There is, however, a
layer of insulating material, placed between the contacting surfaces of the
casting 6 and the annulus 192. To the legs of the casting 6, there is secured a
solenoid supporting plate 7. The plate 7 is, however, insulated from the cast-
ing 6, as indicated in Fig. 1. To the plate 7, a heat shield 13 is in turn secured
by means of screws 131.
Rigidly secured to the inside surface of the casting 6, at the top, is a supporting
tube 8, which extends from the casting 6 downwardly through an aperture in
the plate 7, the construction being such that there is no contact, at any time,
between the tube and plate. To the lower end of the tube 8, is firmly secured
a cap-plate 14. This cap-plate 14 has an inwardly projecting flange a and has
furthermore a thread 141 cast or formed on its exterior surface.
On the top of the cap-plate 12 rests a cylinder of porcelain or other insulating
material, having grooves in its exterior surface, in which grooves a naked helix
of resistance wire is wound. It will be readily understood that the ridges
between the grooves of the porcelain insulate the several turns of the resistance
wire from each other. There is a conducting band 100 which slides up and
down upon the resistance wire and serves to make contact with any given turn
thereof so as to cut into or out of the circuit as many turns as may be desired.

page_text: Against the bottom surface of the cap-plate 14, the inside globe 17 of the
lamp is pressed and is there held by a screw cap 18, which threads upon the screw
thread on the plate 14. The lower edge of the screw cap presses against a
bead 22 on the globe 17. A double sealing of the inside globe 17 is thereby
secured, both at the contacting surface of the globe with the cap-plate and the
contacting surface of the screw cap with the globe and cap-plate.
The carbon carrying tube 9 slides within the tube S. It is guided at the top,
by a ring or projection B secured thereto, and fitting substantially air-tight in
tube 8. At the bottom it is guided by passing in a substantially air-tight fashion
through the orifice in the flange a in the cap plate 14. Secured to the bottom
of tube 9 is a standard 10 on which is pivoted a ring clutch 11 of common form.
The base, against which this ring clutch rests, is formed by a plate 15 secured
on the one side to the negative frame 16 of the lamp and secured on the other
side to the arm 151 which projects downwardly from the cap-plate.
To the upper end of the tube 9 is secured the plunger 26 by means of the
connecting piece 27. The plunger 26 moves up and down within a dash pot 21,
the casing of which is secured to the inside of the casting 6. The casing 21 is
not in electrical connection with the casting 192.
A chain 5 is secured, at one end, to the upper end of the tube 9 and, passing
over a pulley 1, is secured at the other end to the standard 4 which is in turn con-
nected with the armatures or cores 3 of the regulating solenoids or magnets 2.
These solenoids 2 instead of being wound with copper wire are wound with
résistance wire, preferably of German silver, and form part of the necessary dead
resistance of the lamp, when it is used on a constant potential circuit.
resistance wire may be insulated by embedding it in porcelain, by winding it in
grooves on a porcelain cylinder or in any other convenient manner.
The
The outer casing of the lamp may now be described. The upper section, as
shown, consists of four sections 241, 242, 243 and 244, which are secured to each
other by. screws or in any other convenient fashion. The upper section 241, as
shown is secured, by screws, to the top plate 19. The lower sections 243, 244 are
secured to the plate 7 by screws.
The section of the globe casing 245, is secured to the plate 13 at its upper
end. This casing is provided with air vents. Formed in the bottom of this
casing there are bayonet jointed slots for the purpose of securing the globe
holder 246, as will be readily understood. The globe holder 246 carries screws 247
for the purpose of securing the outer globe of the lamp.
The current passes from the binding post 28 which is secured to and insulated
from the top plate 19, down to the solenoids 2 and through to the frame 6. From
this frame 6, the current passes to the tube 9 and through the carbon holder 91
within that tube to the upper carbon. Thence the current passes to the negative
carbon, to the negative frame 16 to the lower terminal 100 of the resistance 12,
and through this resistance to the binding post 20.
The operation of the lamp will now be obvious. The magnets or solenoids 2,
when the current is passed through the lamp, act to strike the arc in a manner
that is well understood and to keep the arc at proper length at all times.
arc being formed in a substantially air tight structure there will be little con-
sumption of the carbons and their life will be long.
The
If the arc is to be used on a constant potential circuit the rheostat 12 is
useful to adjust for the differences between the normal voltage of the lamp and
the voltage of the circuit from which it is fed. By making the feeding or regu-
lating solenoids 2, which are in series, of resistance wire, the amount of wire
which is necessary for the rheostat 12 is considerably reduced.
By insulating the casting 6 from the plates 7 and 19, it will be seen that the
outer casing of the lamp may be fastened to these two plates 7 and 19 without
putting the outer casing in the circuit. The same remark applies to the lower
section of the casing 245 which, being secured to the plate 13, is also out of
circuit. The manner of supporting the rheostat 12 is especially convenient and
A

page_text: the plate 13 acts as a shield to prevent the heat, which is given off from the
rheostat and from the lower globe, from heating the upper part of the lamp. The
plate acts to divert the heated air through the air vents in the casing 245.
It will be noticed that while the cylinder is attached with a double sealing this
also applies to the opening in the cap plate, the bushing here being supple-
mented by the flange extension at the upper end of the carbon carrying tube.
The lamp may also be adapted for other than constant potential circuits, in
which case the supporting magnets would be wound with copper, other suitable
changes in the regulating mechanism also being made without disturbing the
features of the lamp as herein described.
To be able to insert the upper carbon when the lamp is hot the upper carbon
holder tube is provided with an aperture 97 passing through it sidewise, in such a
position that when a wire or small rod is pushed through this hole, the holder will
be locked in position against upward pressure and admit the carbon being forced
into it without the need of holding it stationary with the hands or other tool.
Having now particularly described and ascertained the nature of this said
invention and in what manner the same is to be performed as communicated
to me by my foreign correspondent, I declare that what I claim is:.
1. An arc lamp comprising the combination of a cap-plate, a globe secured
thereto in a substantially air-tight fashion, a carbon carrying tube passing sub-
stantially air-tight through an aperture in the cap-plate and an electro-magnetic
carbon operating device substantially as described.
2. The combination of a cap-plate having an arc enclosing globe secured
substantially air-tight thereto, an outer tube secured to the cap-plate, a carbon
holding tube passsing substantially air-tight through and guided by an aperture
in the cap-plate and having a flange for guiding it and for effecting a seal at its
upper end and electro-magnetic means for operating the carbon holding tube,
substantially as described.
3. An arc lamp comprising the combination of a cap-plate, an arc enclosing
globe secured substantially air-tight thereto, an outer tube secured thereto, a
carbon holding tube sliding at its lower end substantially air-tight within, and
guided by an aperture in the cap-plate, a flange for guiding the upper end of
the carbon holding tube within the outer tube, a pulley, a chain and an electro-
magnet for operating the carbon holding tube, substantially as described.
4. The combination of a cap-plate having an arc enclosing globe secured sub-
stantially air-tight against its under surface and having a hollow rheostat
supported on its upper surface, substantially as described.
5. The combination of a cap-plate having a screw thread on its outer surface, a
globe pressed substantially air-tight against the under surface, and having a
bead, and a screw cap for connecting the parts and effecting a double seal, sub-
stantially as described.
6. The combination of a top plate, a casting secured thereto at its top but
insulated therefrom, a solenoid supporting plate secured to but insulated from
the bottom of the casting and a globe casing secured to the respective plates,
substantially as described.
7. The combination of a top plate, a tube suspended therefrom, a cap-plate
secured to the tube and a solenoid supporting plate secured to and insulated from
the top plate, substantially as described.
8. A top plate, a legged casting and a magnet supporting plate secured to but
insulated from each other, a supporting tube secured, at its top, to the casting
and supporting, at its bottom, the cap-plate for the globe, a carbon-carrying tube
sliding within the supporting tube and an electro-magnet mounted on the sup-
porting plate for actuating the carbon carrying tube, substantially as described.
9. A top plate, a legged casting and an electro-magnet supporting plate
secured to but insulated from each other, a supporting tube connected at its top
with the casting and supporting the cap-plate for the globe, and a rheostat

page_text: surrounding the supporting tube between the cap-plate and the electro-magnet
supporting plate, substantially as described.
10. The combination with the top plate, the electro-magnet supporting plate
and an intervening casting connected thereto but insulated therefrom, a sup-
porting tube connected at the top to the casting and supporting at the bottom
a cap-plate for the globe, a rheostat between the cap-plate and the solenoid
supporting plate and a heat shield above the rheostat, substantially as described.
11. The combination of the top plate, solenoid supporting plate and an inter-
vening casting connected to but insulated from the plates, the solenoid supporting
plate carrying a heat shield and an outer globe casing having its sections secured
to the top plate, the solenoid supporting plate and the heat shield respectively,
substantially as described.
12. The combination of a top plate, a solenoid supporting plate and an inter-
vening casting connected thereto but insulated therefrom, the solenoid support-
ing plate carrying a heat shief, a lamp casing secured to the plates and to the
heat shield respectively and a globe holder secured to the lamp casing, sub-
stantially as described.
13. The combination of the cap-plate having a globe secured to its bottom sur-
face and having a hollow rheostat supported on its upper surface, a carbon
carrying tube moving within the rheostat and a carbon actuating device sup-
ported above the rheostat, substantially as described.
14. The combination of the cap-plate having a globe secured to its under
surface and a hollow rheostat supported on its upper surface, a carbon holder
moving within the rheostat and an electro-magnet, pulley and chain supported
above the rheostat for actuating the carbon holder, substantially as described.
15. The combination of the top plate, an electro-magnet supporting plate and
a casting connected to but insulated from these plates, a tube suspended from
the casting but passing freely through an aperture in the solenoid supporting
plate and carrying a cap-plate at its lower end, a carbon carrying tube moving
within the first mentioned tube and electromagnetic means for operating the
carbon carrying tube, substantially as described.
16. A constant potential arc lamp having its regulating coil in series and wound
with resistance wire constituting a portion of the resistance of the lamp and a
supplementary resistance to adjust for the voltage of the circuit substantially as
described.
17. The combination of a cap-plate carrying a guiding tube, a carbon carry-
ing tube, suspended from its top and carrying a clutch at its lower end, moving
substantially air-tight in the guiding tube, substantially as described.
18. The combination of a cap-plate carrying a guiding tube, a carbon carrying
tube, suspended from its top and carrying a clutch at its lower end, moving sub-
stantially air-tight through a bushing near its lower end and having a flange
at its top fitting the guiding tube in a substantially air-tight manner, sub-
stantially as described.
19. The combination of a cap-plate, a carbon carrying tube moving there-
within and having a locking aperture in its side, substantially as described.
Dated this 11th day of August 1899.
W. P. THOMPSON & Co.,
Agents.