Improvements in Electric Arc Lamps.
Year: 1895

page_text: Date of Application, 19th Mar., 1895-Accepted, 1st June, 1895
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, No. 5699
I have described certain improvements in electric are lamps which have for their
object the production of a simple, compact and durable lamp containing various
novel features of construction which contribute to the attainment of the desired
objects and to the general efficiency of the lamp. The lamp described in the
application referred to is arranged to be hung from a support above it and certain
parts of the structure are so disposed with reference to the position of the arc as
to intercept some of the rays of light which are directed laterally or downward
from the arc. In the present case there are features of construction which resemble
to some extent corresponding features of the lamp described in the application
referred to,.but the present lamp is so arranged that no parts of the structure
shall interfere with the laterally or downwardly directed rays of light, this lamp
being adapted, like the other, to be supported from above. The construction of
the improved lamp will be described in detail hereinafter.
In the accompanying drawings:-
Figure 1 is a vertical.central section of a lamp constructed in accordance with
my.improvements, the carbons and the carbon-supporting arms being represented as:
broken out to save space on the drawing:
Figure 2 is a horizontal-section of the same on the line y-y:
—y: of Figure 1:
Figure 3 is a vertical section through the upper part of the lamp on the-line 3-2
of Figure 2:
The carbons, their carriers and the mechanism for feeding the carbons are
preferably supported upon or by a plate A. The feed controlling mechanism is
located upon the upper side of the plate A and is enclosed by a shell B. The
latter inay support the resistance coil B¹ and may have secured to itself. a hookib,
by which the lamp may be suspended and suitable-binding posts b, b', to which the
terminals of the main line may be connected respectively.
The carbons C, C, are preferably curved and are secured respectively in
holders. D, D'. The: latter are. so. supported as. to swing downwardly toward each
other as the carbons are consumed so that the arc is, formed at a point below the
plate A and below all of the mechanism of the lamp, whereby no obstruction is
interposed in the path of the laterally or downwardly directed rays of light. The
holders D, D', for this purpose are mounted upon arms E,'E', which are preferably
pivoted between vertical flanges a, a', of the plate A. The arms are insulated
from the plate A by washers e, e, and sleeves e¹, e', slipped upon the pivot pins E
and E.
The arms E, E¹, would naturally swing toward each other by reason of their
own weight and the weight of the carbons, but the movement is regulated and
made positive by mechanisin presently to be described. Each plate E and Eis
connected by a corresponding insulated link F, F, to a sleeve G which is mounted
loosely upon a screw-threaded shaft H, the latter being supported to rotate freely
in a suitable bearing carried by the plate A. The sleeve G might be threaded to
engage the shaft H directly, but in order to permit the arms to be swung

page_text: upwardly without rotating the shaft I prefer to make the sleeve G smooth
interiorly and to allow it to rest upon an independent nut 1 which is screw-
threaded to engage the shaft. The bore of the nut is formed as represented in
Figure 1 so that the nut may be tilted upon the shaft to disengage the threaded
portions i, i, from the threads of the shaft. Portions i, ¹, of the bore of the nut
are smooth so that when the nut is tilted from its true vertical position it may be
slipped easily in either direction upon the shaft H. For the purpose
of
maintaining the nut normally in a position to engage the threads of the shaft H
it is provided around the upper end of the bore with a conical flange which enters
a conical recess in the bottom of the sleeve G and thereby holds the nut in true
vertical position whenever the sleeve rests upon it. The nut also is provided with
lugs,, to enter corresponding notches in the lower end of the sleeve G for the
purpose of holding the nut from rotation.
Means similar to those described and shown in the other application referred to
are provided for effecting the rotation of the shaft H so that the carbon holders
may not only be permitted to swing toward each other but are moved positively
toward each other. Upon the other side of the shaft H is fixed a ratchet wheel K
which is adapted to be engaged and actuated by a pawl L. The latter is seated
upon the end of a lever L'. The other end of the lever L' rests against the
armature M of the shunt magnet M¹ so that when the latter is energized the
pawl L advances the ratchet wheel. A spring m acts upon the lever L¹ to move
the armature in the opposite direction. The shunt wire is connected to the coils
of the magnet M' from the main line at any convenient point and thence to an
insulated back contact m¹ which is supported by the armature M mounted on the
magnet M. An insulated contact spring m2 is carried by the post M2 supported
by the plate A. From thence connection is made in any convenient manner to the
other side of the main circuit.
A forked lever N which is pivoted upon a suitable support, embraces the
shaft H just below the ratchet wheel K and at its other end is connected to the
armature N¹ of the series magnet N2. By means of the lever N the shaft H is
lifted bodily when the current is completed through the series magnet and the
arms E, E¹, are swung apart to separate the carbons sufficiently for the formation
of the arc.
→
The connection of the main line to the series magnet N2 is preferably effected
through the resistance B'. From the magnet N' the circuit is continued to the
pivot-pin E and thence through the arm E, holder D, carbons C, C¹, holder D'
and arm E¹ to the pivot-pin E³ from which it is completed by a suitable
conductor P to the other binding post b¹.
The operation of the lamp herein described is in general the same as other lamps
of like character and need not be set forth 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 carbon holders supported to swing
toward each other, a screw-threaded shaft, a travelling nut mounted on said shaft,
means intermediate said put and holders to control the movement of the latter
from the former and means to rotate said shaft, substantially as shown and
described.
2. In an electric lamp, the combination of arms mounted to swing toward each
other, carbon holders supported by said arms, a screw-threaded shaft, a travelling
nut mounted on said shaft, means intermediate said nut and arms to control the
movement of the latter from the former, means to rotate said shaft, a lever
engaging said shaft to move the same longitudinally in its bearings, and a magnet
and armature to actuate said lever, substantially as shown and described.
3. In an electric lamp, the combination of arms mounted to swing toward each
other, carbon holders supported by said arms, a screw-threaded shaft, a travelling

page_text: nut mounted on said shaft, and intermediate means between said nut and arms to
swing the latter, substantially as shown and described.
4. In an electric lamp, the combination of arms mounted to swing toward each
other, carbon holders supported by said arms, a screw-threaded shaft, a travelling
nut mounted on said shaft, a sleeve mounted on said shaft to rest upon said nut
and connections from said sleeve to said arms, said nut having its bore formed to
permit the nut to be tilted upon the shaft to disengage its threaded portions from
the thread of the shaft, substantially as shown and described.
5. In an electric lamp, the combination of arms mounted to swing toward each
other, carbon holders supported by said arms, a screw-threaded shaft, a travelling
nut mounted on said shaft, a sleeve mounted on said shaft to rest upon said nut
and connections from said sleeve to said arms, said nut having its bore formed to
permit the nut to be tilted upon the shaft to disengage its threaded portions from
the thread of the shaft, said nut being also engaged by said sleeve to hold it
from rotation and to maintain it in normal position with its threaded portions
in engagement with the threads of the shaft, substantially as shown and described.
Dated the 18th d... of March 1895.
E. K. DUTTON & Co.,
5, John Dalton Street, Manchester, Agents.
E. K. DUTTON & Co.,
5, John Dalton Street, Manchester, Agents.