Improvements in Electric Arc Lamps.
Year: 1897

page_text: Date of Application, 29th June, 1897-Accepted, 14th Aug., 1897
COMPLETE SPECIFICATION.
Improvements in Electric Arc Lamps.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention (which has been communicated to me from abroad by The General
Incandescent Are Light Company Limited, of 072 First Avenue, City of New
York, United States of America) and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement:
The invention relates to various constructive details of electric arc lamps, par-
ticularly such as have an inner globe, comprising an adjustable cover and vent for
the inner globe, fastening and adjusting means for this globe, devices for
suspending and adjusting the outer globe and a clutch for holding and feeding the
movable carbon, as will be described referring to the accompanying drawings.
Figure 1 is a vertical section of one form of lamp showing certain features of
this invention, the inner globe being shewn in elevation; Figure 2 is a vertical
section of the lower part of a modified form of the lamp; Figure 3 shows in section
details of the clutch for the upper carbon; Figure 4 is an enlarged section shown-
ing the means of fastening both globes and the lower carbon; Figure 5 is a
section of another form of the means for supporting and adjusting the outer globe;
Figure 6 is a plan partly in section of a portion of the clutch; Figure 7 is a
vertical section of the cover for the inner globe; Figures 8 and 9 show on an
enlarged scale. the means of adjusting and fastening the inner globe and lower
carbon; Figure 10 is a sectional plan of the lower carbon fastener; and Figure 11
is a plan of the upper end of the bolt supporting the outer globe, and the seats for
the bolt.
1 is an elastic spreading skirt or covering: rim, into which the upper part of the
outer globe 2, is inserted with sufficient force to exclude aust, rain, &c. As shown
in Figure 4 the lower edge of the outer globe 2 rests, preferably upon a yielding
pad' or washer, 3, in the supporting saucer, 4, and is held by a screw 5.
The saucer, 4 is carried on a bolt, 6, passing through it, and supported by pins 7.
In raising the globe to operative position, after cleaning, the bolt, 6, is turned so
that the pins 7 can pass through grooves, 8, (Figure 11) in the bracket, 9. As
shown by dotted lines in Figure 4, one side of each of these grooves 8, is higher
than the other, and the supplemental pins, 7, are so placed that the pins 7, cannot
pass beyond these higher shoulders, but can pass over the lower sides of the
grooves 8, and; by turning the bolt 6, as far as permitted by a shoulder the pins 7
can be made to lie in the seats 13, preventing the bolt 6 from being turned when
the nut, 11, is turned. This nut screwed on the bolt 6 supports the saucer 4. By
turning the nut 11 on the bolt, 6, after the pins 7, are in their seats 13, the globe is
gradually raised and forced into the resilent skirt 1.
The pins 7 may serve to limit this upward movement of the globe and prevent
excessive pressure upon its upper rim in case of careless handling. A lock nut 12
may be employed to prevent accidental unscrewing of the nut 11.
A special and compact construction for fastening both the lower carbon and
inner globe is shown in detail in Figures 4, 8, 9 and 10.

page_text: This consists in a cylinder 14, insulated from the bracket 15, by which it is
supported. Through this cylinder, the lower carbon passes, and the setting
screw 16 fastens it. A swinging door 17, pivoted at one side under 14, as shown
at 18 in Figure 9, serves to exclude dust, rain, &c., and acts also as a temporary
support for the lower carbon, till the screw 16 is turned.
In order to fasten the inner globe, the cylinder 14 is screw threaded at its upper
end. This thread is preferably made by stamping a metallic thimble 20, which
bas a circular flange 21, for receiving the lower end of the inner globe, and is
forced on to the top of the cylinder 14.
In order to fasten this inner globe, a threaded shell 22, coned so as to exert
progressively increasing pressure on the inner surface of said globe, is screwed
down upon 20. The cylinder 14 may be fastened in any desired manner to its
support 15, as shown in the drawings it is held by a pair of screws, 23, passing
through a lateral extension of the cylinder. By means of one of these screws the
current may be led directly through the cylinder to the lower carbon.
In Figures 3 and 6, is shown a special clutch for the gradual feeding of the
upper carbon.
To the core of a solenoid forming the usual carbon support, is
pivoted a pair of links 24, having jointed to them levers 25, having shoes or
jaws 26, to press on the carbon which passes through a disc or plate 27, having
lugs on which the levers 25 are pivoted. Beneath the disc 27 several projecting
pins 28, form stops limiting the downward movement of the clutch, whereupon.
the shoes or jaws 26 move slightly apart releasing the carbon. When the carbon
descends the resistance of the arc is lessened and the clutch rises clamping the
carbon and preventing its farther descent.
Figure 7 shows means of closing the top of the inner globe, which should be
kept closed as far as possible with provision for escape of air and gases upon
expansion due to heat.
I
For this purpose a loose cover 29, of some weight, has a flunge 30 which normally.
closes the top of the globe. The upper carbon passes through this cover, and certain
play is given by making the portion 31, of the cover within the globe of somewhat
less diameter. The pressure of the gases in the inner globe may be regulated by
the weight of the cover 29.
Figure 5 shows a modified arrangement whereby the saucer 4 may be supported
in such a manner as to permit of the gradual lifting of the globe into the skirt 1.
In this case the threaded tube 32 holds the lower carbon, and a uut 33 passing
through the saucer 4 so as to support said saucer upon its shoulder 34 is screwed
on to the tube 32 raising the globe. The nut can turn independently of the
saucer 4. A chain 35 prevents accidental falling of the globe or saucer.
Having now particularly described and ascertained the nature of this in-
vention and in what manner the same is to be performed, I declare 'that what I
claim in respect of an electric arc lamp is:-
1. A cap through which the upper carbon passes, having a flange resting on
the inner globe and having an inwardly projecting part slightly smaller in
diameter than the globe aperture, so as to perinit lateral play of the carbon,
substantially as described.
2. A feeding device comprising a pair of links pivoted to the movable, core of
a regulating solenoid and connected by levers to a pair of jaws clamping the
carbon, these levers being pivoted on a disc through which the carbon passes, and
which has its descent limited by stops substantially as described.
י
3. The support for the globe, the hanging rod or bolt bearing such support
and lugs at its upper end in combination with a supporting bracket having grooves
and seats to receive lugs and stop pins on the hanging rod substantially as and for.
the purpose set forth.
4. The combination of a tube for receiving the lower carbon, a globe adapted
to rest over the tube, and a thimble adapted to screw on the tube; this.thimble

page_text: being coned at the top so as to fit into the bottom of the globe substantially as
described.
5. The combination of the outer globe, the main frame and skirt against which
the
upper part of the globe is pressed, the support for the globe, a screw threaded
hanging rod passing through the support, the nut on the rod for raising the
support,, and a stop pin for limiting its ascent, substantially as described.
6. An electric are lamp constructed and operating substantially as described
with reference to the accompanying drawings.
ABEL & IMRAY,
Agents for the Applicant.