Improvements in Electric Arc Lamps.
Year: 1899

page_text: Date of Application, 30th Oct., 1899-Accepted, 23rd Dec., 1899
COMPLETE SPECIFICATION.
Improvements in Electric Arc Lamps.
We, THE BRITISH THOMSON-HOUSTON COMPANY, LIMITED, of 83, Cannon Street,
in the City of London, Electrical Engineers, do hereby declare the nature of our
said inventión (which has been communicated to us from abroad by Charles E.
Harthan and George E. Stevens, both residing at Lynn, in the County of Essex,
State of Massachusetts, United States of America, Electrical Engineers), and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
Our invention relates to electric arc lamps, and more particularly to those of
what is commonly known as the "enclosed" type, and consists in the parts and
combination of parts as hereinafter described and claimed, designed and
arranged to improve the construction and operation of the lamps.
In the accompanying drawing, which illustrates an embodiment of our inven-
tion, Fig. 1 is a front elevation, partly in section, of the globe supporting devices
of an arc lamp; Fig. 2 is a detail; Fig. 3 is a cross section of the yoke and
holder, and Fig. 4 is an enlarged detail.
Extending downward from the base C are the side tubes A and B, and con-
necting these tubes at the lower end is a spring supported yoke D. Mounted for
vertical movement within the tubes are the globe-carrying rods E and F, which
are connected by the cross-bar G. Secured to and extending downwardly from
the cross piece G is a screw threaded stud H, and mounted upon the stud is the
outer globe holder I. No means are shown for locking the rods E and F in their
raised position, but it is to be understood that they will be secured in the ordinary
manner.
Adjustably mounted on the side tubes at a point below the base, and insulated
therefrom, is a flat metal plate or cap J, which is provided in the centre with a
device K for preventing the free entrance and exit of air to the cylinder or
globe L. On the ends of the plate or cap are sleeves J which are insulated
therefrom by insulating bushings M, and mounted within the sleeves are metal
linings N, which surround the tubes A and B. The plate J may be adjusted
upon the tubes by releasing the screws J2 which are mounted in bosses formed
on the sleeves; it is not intended, however, to adjust the plate or cap each time
a cylinder L is inserted, but only when cylinders of different heights are used.
The yoke D is provided with two cup like cavities on the top side for the recep-
tion of the side tubes A and B, and situated directly below these cavities are other
cavities each being somewhat larger than those first mentioned and containing a
securing screw 0 and a coiled compression spring P. The screws 0 are some-
what large and are bored out as shown in Fig. 4, to permit the globe supporting
rods to pass freely through them, and their hands act as shoulders against which
the springs abut. With this arrangement the yoke D always presses the
cylinder L upward against the under side of the plate J, and is capable of a
slight movement independent of the side tubes. The yoke D forms a seat for
the cylinder support L' and is provided with a straight bore D1 and a conical
bore Da, to receive the conical or tapered portion L2 of the cylinder support L';

page_text: and between the two parts is a metal bushing L³ serving to increase conductivity
between the lower carbon P¹ and the yoke D. The yoke is cut away on the front
side, as shown at 13 in Fig. 2 so that by separating the support or cylinder
holder L and the yoke, as for example by depressing the yoke by hand, the
cylinder holder may be moved bodily to the front and removed together with
the cylinder L and the lower carbon. The shape of the parts is such that the
holder cannot by any chance slip out sidewise in the normal action of the lamp,
but when the parts are separated by, a sufficient distance, the cylindrical part on
the lower end of the holder will slip sidewise through the opening D³.
Mounted within the cylinder support in any suitable holder, is the lower
carbon 1", and in the present instance a thumb screw is employed to permit
the centering of the carbon and also to establish good conductivity between the
holder and the carbon.
"
No special clamping means are employed to hold the cylinder either at the top
or bottom; the bottom is seated on a bed or packing of asbestos L; and held from
moving eccentrically with respect to the carbon by the upturned 'flange 7! on the
holder. This is a very simple arrangement, and permits of the ready removal
and substitution of a new carbon and cylinder.
If desired, the cylinders may be cleaned at the station and carbons placed 'in
the holders, so that the operation of trimming a lamp may consist only in in-
serting a new upper carbon and slipping in a new cylinder.
The upper carbon P is mounted within the carbon tube R, and projects down-
ward through the plate or cap J into the cylinder L, and in retrimming is pushed
upward through the yoke D. To permit this insertion, and also to strengthen
the yoke, a flat web 13 is formed integral with the yoke.. This web is provided
with a central opening through which the carbon can be passed from the 'under
side of the lamp. Mounted on the lower end of the tube R is a clutch S which
grips the upper carbon and controls its feed. The clutch arms are arranged to
strike on the plate J, which acts as a tripping platform.
:
Current may be conveyed to the lower carbon through the side tubes, or a
separate connection may be employed, which connects, with the lower carbon-
holder, in which case the latter would preferably be insulated from the yoke D.
Having now particularly described and ascertained the nature of our säid
invention (as cominunicated to us from abroad) and in what manner the same
is to be performed, we declare that what we claim is:-
1. In an electric arc lamp, the combination of a yoke, a support therefor, an
arc-enclosing cylinder, a cap therefor carried by the support, and coiled springs
which tend at all times to force the yoke and cap toward each other.
2. In an electric arc lamp, the combination of a pair of downwardly extending
supports, a yoke connecting the lower ends of the supports, an arc enclosing
globe or cylinder, a cap for the cylinder carried by the downwardly extending
supports, a holder for the bottom of the cylinder a seat formed in the yoke, and
coiled springs for forcing the cap and the top of the cylinder together.
3. In an electric are lamp, the combination of a tubular side rod, a yoke carried
thereby, and are enclosing cylinder, a cap therefor mounted on the side rod and
capable of vertical adjustment, a holder for the cylinder, a seat in the yoke for
the holder, and a coiled spring surrounding the side rod and tending at all times
to press the cap and yoke together.
4. In an electric are lamp, the combination of a downwardly extending side
rod; a yoke mounted on the bottom of the rod, a cylinder cap, and a sleeve for the
cap, which surrounds the side rod and is insulated from the cap.
5. In an electric arc lamp, the combination of a pair of tubular side rods,' a
roke connecting the rods, which is provided with cup-shaped cavities on the
upper side for receiving the ends of the rods and with similar cavities on the
under side thereof, means for securing the yoke to the rods, and springs for per-
mitting a slight movement of the yoke independent of the rods.

page_text: 6. In a lamp, the combination of a pair of side rods, a yoke connecting the
rods at the bottom and provided with a seat which has an opening at one point,
a fixed top or cap for the cylinder, and means permitting the removal of the
cylinder by slightly depressing the yoke.
7. In a lamp, the combination of a pair of side rods, a spring-supported yoke
connecting the rods and provided with a seat having a straight and conical bore,
the said seat being cut away at one point, a cylinder and a holder therefor, having
a base formed to fit the seat in the yoke.
8. As an article of manufacture, a yoke for an electric arc lamp, having top
and bottom cup-shaped cavities at each end, a combined straight and conical
bored seat which is cut away at one point, and a flat web situated below the seat
and provided with an opening to permit a carbon to be passed upward through
the yoke.
9. In an electric arc lamp, the combination of a pair of tubular side rods, a
yoke connecting the rods, screws threaded to the lower ends of the rods, and
compression springs surrounding the screws and arranged to force the yoke up-
ward against the ends of the side rods.
10. In a lamp, the combination of a pair of side-rods, a spring supported yoke
connecting the rods, a cylinder, a fixed cap, and a seat for the lower end of the
cylinder, which is provided with an opening on one side, the arrangement of
parts being such that the cylinder can be removed only by depressing the yoke
and removing the lower end of the cylinder through the opening in the seat.
11. In an electric arc lamp, the combination of an inner globe or cylinder
which is open at both ends, a cap or cover for the top, a holder in which the
lower end of the cylinder rests but is not clamped, and means for pressing the
cap and holder against the ends of the cylinder to hold the latter in place.
Dated this 25th day of October 1899.
MSON-HOUSTON Co., LTD.,
J. J. MANHEIM,
A. R. MONKS,
}
Directors.
Assistant Secretary.
ALFRED CLEMENTS,
THE BRITISH THOMSON-HOUSTON Co., LTD.,
J. J. MANHEIM,
A. R. MONKS,
ALFRED CLEMENTS,
Directors.
Assistant Secretary.