Improvements in Electric Lamps or Lighting Apparatus.
Year: 1888

page_text: Date of Application, 19th Nov., 1888
Complete Specification Left, 19th Aug., 1889-Accepted, 28th Sept., 1889
PROVISIONAL SPECIFICATION.
Improvements in Electric Lamps or Lighting Apparatus.
I, ALFRED LYSTER SHEPARD, of 8 West Kensington Gardens, in the County of
Middlesex, Electrical Engineer, do hereby declare the nature of this invention to be
as follows:-
My invention relates to electric lamps, or lighting apparatus and more especially
to electric arc lamps.
The main object of my said invention is to provide improved means for ensuring
the maintenance of the luminous point in an electric arc lamp in the same position or
in approximately the same position in the globe during the consumption of the
carbons.
In carrying my said invention into practice I provide a globe the upper part or
portion of which is provided with a suitable metal ring or collar having two or other
suitable number of projections. These projections are provided with grooved wheels
or pulleys. Suitable wires or chains attached at one extremity to non conducting
pieces or blocks provided in the frame of the lamp, or otherwise suitably insulated
therefrom, pass round these grooved wheels or pulleys and are attached at their other
extremities to non conducting pieces or blocks provided in the upper carbon holder or
are otherwise suitably insulated therefrom. It will be seen that the globe is supported
by the above mentioned wires or chains.
are fed downwards to
When the upper carbon holder, and carbon descend or
compensate for the consumption of the carbons, the globe will also descend or
travel downwards owing to the extremities of the wires or chains attached to the
said upper carbon holder descending with it.
I sometimes attach the extremities of the wires or chains to the upper carbon
holder and pass the said wires or chains over grooved wheels or pulleys provided upon
the frame of the lamp. The other extremities of the said wires or chains are
attached to the lower carbon holder. Non conducting blocks or pieces or other
suitable means for insulating the said wires or chains from the said carbon holders are
moreover provided. As the upper carbon.holder descends or is fed downwards to
compensate for the consumption of the carbons the said upper carbon holder will also
pull down or carry with it the extremities of the said wires or chains attached thereto,
and will therefore cause the other extremities of the said wires or chains and
consequently the lower carbon holder to rise. The luminous point will thus be
maintained constantly in the same position, or approximately in the same position in
the globe of the lamp.
My said invention is applicable to any suitable arrangement of arc electric lamp.
When my improved device is applied to an arc electric lamp in which no provision is
made for the difference in consumption of the carbons 1 provide any suitable means
for causing the globe to descend in accordance with the descent of the luminous
point.
By my invention I provide for maintaining the luminous point in the same or
approximately the same position in the globe of the lamp, in an exceedingly simple
and inexpensive manner, and without the employment of any more or less complicated
mechanism. I am thereby enabled to employ a smaller globe than is required in the
arc electric lamps as usually constructed. Moreover by the employment of a smaller
globe there is a considerable saving in the consumption of carbons. I sometimes
when my improved lamp is intended to be used out of doors, employ an outer globe
or any suitable shield or guard for protecting it from the weather.
Although I have hereinbefore described convenient and advantageous methods of
carrying my said invention into practice it is obvious that I can somewhat modify the

page_text: construction of my apparatus without departing from the nature of my said invention.
For example I can in cases where the lower carbon holder is fed, or caused to travel
upwards in order to compensate for the consumption of the carbons and the upper
carbon holder remains stationary, cause the globe to ascend or travel in an upward
direction instead of downwards. Instead of the wires or chains hereinbefore described
I can employ cords formed of any suitable material. I sometimes moreover employ
the herein-before mentioned wires or chains as conductors. In this case the said
wires or chains are electrically connected to the main conductors in any suitable
manner.
Dated thig 19th day of November 1888
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Electric Lamps or Lighting Apparatus.
I, ALFRED LYSTER SHEPARD, of 8 West Kensington Gardens, in the County of
Middlesex, Electrical 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 :-
My invention relates to electric arc lamps or lighting apparatus.
The main object of my said invention is to provide in a simple and efficient manner
'for ensuring the maintenance of the arc or luminous point in a central, or nearly
central, position within the globe, notwithstanding the feeding of the carbon or carbons
to compensate for the consumption of the same.
For this purpose, I so construct the lamp or lighting apparatus that, as the carbons
are consumed and the arc is moved by the feeding of the said carbons, the globe will
move in correspondence with the arc.
I prefer that the carbons should be arranged vertically and that the lower carbon-
holder should be fixed or stationary, the upper carbon-holder being provided with
means for feeding it downward as the carbons are consumed. In this case, I suspend
the globe by means of cords, wires or chains from the lamp-frame and from the upper
carbon-holder in such a manner that, as the said carbon-holder descends or is fed
'downward, the globe will also descend by gravity, but only through one-half of the
distance traversed by the carbon-holder, that is to say, the velocity of the globe will
he equal to one-half of that of the carbon-holder. Other suitable means may,
however, be employed for effecting the requisite movement of the globe, according
to the construction and arrangement of the other parts of the lamp or lighting
apparatus.
In the accompanying drawing, I have shown one form of my improved electric
lamp or lighting apparatus.
a is the lamp-frame, 6 the upper carbon-holder, 6¹ the lower carbon-holder,
c, c¹ are the carbons; d is the globe. The upper part of the said globe has secured
thereto a metal ring or collar e having two or more arms or projections e¹ provided
with grooved wheels or pulleys f. Around these grooved wheels or pulleys are
passed cords, wires or chains 9 which at one extremity are attached to non-conducting
pieces or blocks h provided in the lamp-frame a, or are otherwise suitably connected
with, but insulated from the said frame, and at the other extremity are attached to
non-conducting pieces or blocks; provided in a cross-bar & secured to the upper
carbon-holder or are otherwise suitably connected with but insulated from the said
*holder.
The globe is supported by the said cords, wires or chains. When the upper carbon
and carbon-holder descend or are fed downwards to compensate for the consumption
of the carbons, the globe will also descend under the action of gravity at one-half
of the speed of the said carbon and carbon-holder, the luminous arc will therefore
always be kept in a central, or nearly central, position within the globe.

page_text: With a lamp or lighting apparatus constructed as above described, a globe can be
used of much less diameter than those usually employed in electric arc lamps as
beretofore constructed.
My said invention is applicable to any suitable arrangement of arc electric lamp.
When my improved device is applied to a lamp in which no provision is made for any
difference in consumption of the carbons, I substitute for the cords and pulleys
arranged as above described, other suitable means for causing the globe to move with
the arc.
By the employment of a smaller globe than is generally used, I effect a considerable
saving in the consumption of carbons. I sometimes, when my improved lamp is
intended to be used out of doors, employ an outer globe or a suitable shield or
guard for more effectually protecting the lamp.
It is obvious that I can somewhat modify the construction of my apparatus if
desired. For example, in lamps wherein the upper carbon-holder is stationary, and
the lower carbon-holder is fed or caused to travel upwards to compensate for the
consumption of the carbons, I can so construct and arrange the parts that the
globe will ascend or travel upward instead of downward, suitable counterweights
being connected with the lower carbon-holder.
I sometimes employ the aforesaid wires or chains as conductors, in which case
they are electrically connected with the main conductors in any convenient manner.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I wish it understood that I
claim:
First. An electric lamp or lighting apparatus wherein the globe is arranged to move
with the arc as the carbons are consumed, for the purpose above specified.
Second. The improved means, substantially as described with reference to the
accompanying drawing, whereby I provide for maintaining the arc in a central, or
nearly central, position within the globe.
Dated this 19th day of August 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.