Improvements in Electric Arc Lamps.
Year: 1895

page_text: Date of Application, 19th Mar., 1895-Accepted. 15th June, 1895
COMPLETE SPECIFICATION.
Improvements in Electric Arc Lamps.
I, GEORGE ROBERT MACINTIRE, of No. 413 West 25th Street, in the City
of New York, and County and State of New York, United States of America,
Mechanical 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 :-
In another application for Letters Patent filed concurrently herewith, 5699,
I have described certain improvements in electric are lamps, which have for their
object the production of a compact lamp, containing various novel features of
construction. The lamp there described is particularly adapted for a pendent
lamp and is provided with but a single pair of carbons. In the present application
I describe a lamp which embodies some of the general features of the other lamp
referred to but differs in certain details of construction and particularly in that it
is provided with a plurality of pairs of carbons the feed of which is controlled and
determined by a single set of feeding mechanism. Moreover the lamp herein
described is represented as adapted to be supported from beneath upon a standard
or upon a bracket.
In the accompanying drawing in which is illustrated a lamp embodying the
present improvements :-
Figure 1 is an elevation of the improved lamp, the shell which protects the
feeding mechanism being shown in section and some other parts being broken out
to save space:
Figure 2 is a horizontal section on the line - of Figure 1:
Figure 3 is a vertical central section of the lamp, some parts being broken away
to save space:
Figure 4 is a section on the line y-y of Figure 1, the direction of sight being
upward:
Figure 5 is a section on the line - of Figure 1, looking upward.
The feeding mechanism and other parts of the lamp are supported by a base A
which is adapted to be set in a socket suitable for its reception or to be otherwise
secured to a standard or bracket and comprises a plate A', a protecting shell A²,
and an annulus or bottom piece A³ by which the magnets are supported within the
shell A
To the plate A' are secured two or more sections B, B', which together make up
a supporting and guiding sleeve and separately constitute parts of the circuit, the
said sections being insulated from the plate A' and from each other. At their
upper ends the sections are secured together, being still insulated from each other,
by a suitable cap-piece B. Within the sleeve B, B', a shaft C having a spiral
groove e, is mounted to rotate freely and at the same time to have capacity for a
limited vertical movement. The upper end of the shaft C may be guided by a
pin b which is carried by a screw fixed in the cap-piece B2. The shaft is
supported vertically by the armature of the series magnet, preferably resting upon
the point of an intermediate rod C₁ which is fixed to or in turn rests upon said
armature. Means are provided, as hereinafter described, for rotating the shaft C
and upon said shaft is mounted a driving nut D which is connected by webs or
arms d, d, with a carriage E, E', which slides freely upon the outside of the
composite sleeve B, B. The carriage is made up of the two sections E, E', which
are insulated from each other and are also insulated from the nut D, the contact of
[Price 8d.]

page_text: each section E, E',, with the corresponding section of the sleeve B, B3, being
assured by a spring e which is fixed to the respective section of the carriage and
bears upon the corresponding section of the sleeve.. The vertical edges of the
section E, E, of the sleeve or tube are separated by a sufficient distance to prevent
the leaping of the current from one to the other and also to permit the free move-
ment of the webs or arms d, d. The section E of the carriage E, E', has an
arm E which supports one upper carbon holder E and the other section E in
similar manner is provided with an arm E³ which supports the upper carbon
holder E. The lower carbon holder F, which corresponds to the upper carbon
holder E is supported by an arm F2 from the plate A', the said arm being insulated
from the plate. In like manner the lower carbon holder F¹ which corresponds to
the upper carbon holder E' is supported by an arm F³ from the plate A' said
arm F being also insulated from the plate A¹.
The series magnet G is supported by the bottom piece or annulus A³, being
preferably secured to a vertical flange A' of said bottom piece and being preferably
of the kind commonly known as the iron-clad magnet, having a jacket g which is
connected with the core g¹. The armature H of the series magnet is formed as a
disc which covers the lower end of the magnet, and, as herein before stated, supports
the rod C and the shaft C, whereby, when the current is completed through the
series magnet and the armature H is attracted, the shaft C, the carriage E, E',
and the upper carbon holders E', E' will be raised sufficiently to separate the
pper carbons from the lower carbons for the formation of the arcs.
Upon the series magnet G is supported the shunt magnet I, the latter being
held in position by a disc J having a double flange j, j. The lower flange fits
upon the upper end of the magnet G while the upper flange receives the lower end
of the magnet 1. The magnet I is also preferably of the iron-clad variety, having
a jacket i connected with the core i¹. Both cores g and are bored axially for
the reception of the rod C'.
The shaft C has fixed thereto a ratchet wheel K which is engaged and rotated
by a pawl L. The latter is pivoted upon the end of the armature M of the shunt
magnet and is pressed by a spring 7 into engagement with the ratchet wheel.
The armature itself is pivoted near the periphery of the magnet I and is normally
held away by a spring m from the head of the jacket i and the head 3 of the
core The armature bears an insulated spring contact piece m¹ which is
connected with the coil of the magnet and upon a suitable post N is mounted an
insulated back contact n which is electrically connected in any convenient manner
to one side of the main line, while the other end of the coil of the magnet I is
connected to the other side of said main line.
In the plate A' is mounted a short shaft O, being provided above the plate with
a thumb-piece O' and below the lower plate with an arm O having a tooth O³.
The shaft is acted upon by a spring 0 (shown in dotted lines in Figure 1) to hold
the tooth in engagement with the ratchet wheel K and thus to constitute a hold
pawl to prevent backward movement of said ratchet wheel. By a partial rotation
of the shaft O by means of the thumb-piece O' the tooth O³ may be made to engage
the pawl L and disengage the same from the ratchet wheel to permit the free
rotation of the shaft H when the carriage E, E', is raised by hand.
One terminal of the main line is connected to a binding post P and thence to the
series magnet G. From the series magnet connection is made by a suitable con-
ductor p to one section B of the sleeve B, B¹. From thence the circuit is continued
through the section E of the carriage, arm E2, upper carbon holder E, lower
carbon holder F across the arm F and an intermediate conductor to the other
section B¹ of the sleeve B, B¹. From this point the circuit is completed to the
section E of the carriage E, E¹, arm E³, upper carbon holder E', lower carbon
holder F, arm F³, and conductor pl to the binding post P¹ to which the other
terminal of the main line is connected.
It will be obvious that the supporting and guiding sleeve and the carriage
might be made in any desired number of sections within reasonable limits, and that

page_text: therefore the lamp may be provided with a corresponding number of pairs of
carbons the feed of all of which would be controlled by a single shaft C and its
actuating mechanism, although I have represented but two pairs of carbons. It
will be obvious also that in this case, as in the lamp shown in the other application
referred to, the upper carbons may descend by gravity but that the carriage
supporting them is positively advanced by the action of the pawl L. The operation
of this lamp is substantially the same in general as that of other lamps of like
character and need not be further described herein.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is.
1. In an electric lamp, the combination of a series magnet and a shunt magnet
mounted axially one upon another, with their cores in line, a spirally grooved
shaft supported by the armature of the series magnet in line with the axis of said
magnets, a ratchet wheel fixed to said shaft, au armature for the shunt magnet
pivoted near the circumference thereof to swing across its end and having an
actuating pawl for said ratchet wheel, and a carbon carrier having a nut to engage
said shaft, substantially as shown and described.
2. In an electric lamp, the combination of a carriage composed of insulated
sections, a carbon holder carried by each section, a spirally grooved shaft engaging
said carriage to move it progressively, and independent electrical connectors for the
several sections of the carriage, substantially as shown and described.
3. In an electric lamp, the combination of a supporting base, a sleeve mounted
on said base and composed of insulated longitudinal sections, a carriage mounted
to slide on said sleeve and composed of insulated sections in contact respectively
with the sections of said sleeve, carbon holders carried by the sections of the
carriage, other corresponding carbon holders, and a single feeding mechanism for
actuating said carriage, substantially as shown and described.
4. In an electric lamp, the combination of a supporting base, a sleeve mounted
on said base and composed of insulated longitudinal sections, a carriage mounted
to slide on said sleeve and composed of insulated sections in contact respectively
with the sections of the carriage, other corresponding carbon holders, a spirally
grooved shaft mounted to rotate in said sleeve and adapted to actuate said
carriage, and means to rotate said shaft, substantially as shown and described.
5. In an electric lamp, the combination of a supporting base, a series magnet
supported therein and bored axially, an armature placed below said magnet and
having a rod extending up through the bore of the magnet, a carbon supporting
carriage, a guide therefor, an actuating shaft therefor supported on said rod, and
means to actuate said shaft, substantially as shown and described.
Dated the 18th day of March 1895.
E. K. DUTTON & Co.,
5, John Dalton Street, Manchester, Agents.