IMPROVEMENTS IN ARC ELECTRIC LAMPS
Year: 1882

page_text: LETTERS PATENT to Percy Ruskin Allen of Victoria Works Belvedere Road
Lambeth in the County of Surrey, for an Invention of "IMPROVEMENTS IN
ARC ELECTRIC LAMPS."
PROVISIONAL SPECIFICATION left by the said Percy Ruskin Allen at the
Office of the Commissioners of Patents on the 26th August 1882.
PERCY RUSKIN ALLEN of Victoria Works Belvedere Road Lambeth in the County
of Surrey IMPROVEMENTS IN ARC ELECTRIC LAMPS "
"
My Invention has for its principal object to preserve the moving parts of arc
electric lamps from dirt or corrosion so as to render unnecessary the frequent
cleaning of the said parts which is at present needed.
According to my said Invention I enclose the regulating mechanism in an air-
tight box or casing and I cover the external portion or portions of the rod or rods
of the carbon holder or holders of the parts where they project from the said box
with an envelope stocking or covering attached air tightly at one end to the casing
and at the other end to the outer end of the rod or holder-This envelope is so
constructed or made of such material that it will yield or collapse and extend to
allow of the necessary movements of the carbon holders
In order to operate the tension regulating spring or other required portion of the
apparatus contained in the box or casing I fix a flexible piece of material air
tightly over air opening in the said casing over the operating device so that it
can be operated without opening the box or casing.
The said box or casing may be provided with an opening or openings over which
a flexible bag in communication with the interior of the box is fixed air tightly-
This bag expands or the pressure of air increased in the box thereby giving
virtually a larger capacity to the interior of the said box.
The holder for the carbon may be constructed as follows-to give a ready means
of inserting and removing carbons-The carbon is held between a rigid and a
moveable jaw-This moveable jaw is hinged to the holder and passed upon the
carbon to retain it in position by an annular spiral or equivalent spring passed
around the two jaws-The carbon may be readily withdrawn by simply pulling it
from the holder and another may be reinserted simply by holding open the moveable
jaw and putting the carbon in place after which on the jaw being released the
carbon is held firmly in place

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Percy Ruskin Allen in the Great Seal Patent Office on the
26th February 1883.
PERCY RUSKIN ALLEN of Victoria Works Belvedere Road Lambeth in the County
of Surrey "IMPROVEMENTS IN ARC ELECTRIC LAMPS "
My Invention has for its principal object to preserve the moving parts of arc
electric lamps from dirt or corrosion so as to render unnecessary the frequent
cleaning of the said parts which is at present needed.
According to my said Invention I enclose the regulating mechanism in an air
tight box or casing and I cover the external portions of the rod or rods of the
carbon holder or holders at the parts where they project from the said box with
an envelope, stocking, or covering attached air tightly at one end to the casing and
at the other end to the outer end of the rod or holder.
And in order that my said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of Drawings the same letters of reference
indicating corresponding parts in all the figures.
Figures 1 and 2 of the accompanying drawings are elevations at right angles
to each other of a Brush lamp having two sets of carbons and provided with my
improvements.
A is the air tight box enclosing the regulating mechanism. To this box are
attached the flexible coverings B one for each of the upper carbon holders the said
coverings being attached at one end b to the box A and at the other end b² to the
carbon holder. This covering may be made of any such form and material as will
yield or collapse and extend to allow of the necessary movements of the carbon
holders I have shewn in the drawing the said covering as being of a construction
resembling that of concertina bellows. When in this form its angles are preferably
provided with rings of metal wire as shewn in Figure 3 or discs as in Figure 4.
These angular portions may have a helical form when the rings will be replaced by
spiral wires as shewn in Figure 5 but I wish it to be understool that I have only
shewn these as illustrations of a convenient form of coverings and do not limit
myself thereto.
Figures 6 and 7 represent respectively a Jasper Lamp and a Crompton Lamp
provided with a similar air tight casing A and at B with similar coverings for the
parts which extend to outside the said casing A. The material of the coverings
may conveniently be the waterproof material known as mackintosh but it may as
before stated be of any suitable material. Where two or more sets of carbons are
used a sheet of talc or other material may be provided as at C. Figures 1 and 2 to
protect the coverings from the heat of the carbous. Where a single pair of carbons
is used a convenient guard may be provided as at C2. Figure 7 and this may of
course be applied to each holder of a lamp having more than one set of carbons.
In order to provide for operating the tension regulating spring or other required
portion of the apparatus contained in the box or casing A without destroying the
air tight character of the said box or casing I fix a piece of flexible material (such
for example as the before mentioned mackintosh) airtightly over an opening in the
said casing over the operating device as at d Figure 1. Figures 8. 9 and 10 are
enlarged views of this detail. In Figure 10 the flexible material d is fastened to
the casing by a ring or flange piece d² extending around the opening, and caused
by screws or the like to pinch the flexible material between itself and the said
edge. A cross bar 3 carries a screw d' To alter the tension of the spring e the

page_text: said screw presses inwards the flexible material d and causes a stud d³ to bear on
the end of the bell-crank lever f. Figures 8 and 9 are views at right angles to
each other (the latter being an inside view) in which the flexible material d covers
a curved slot a and through the said material the projection g² from the lever g
can be felt and operated. The tension of the spring is altered simply by pressing
the projection g² to one side or the other to turn the spindle g³ and alter the position
of the eccentric g' to adjust the spring-In order to prevent the confined air in
the box A exerting an inconvenient pressure by the moving of the parts inside it; I
provide the said box with an opening or openings over which a flexible bag (as at h
Figure 6) is fixed air-tightly. This bag expands as the pressure of the air increases
in the box thereby compensating for the entry of any of the parts into the
casing and giving virtually a constant capacity for the air. The holder for the
carbon may be constructed as shewn in elevation and plan of underside in Figure 11
to give a ready means of inserting and removing the carbon. The carbon i is
held between a rigid jaw j and a moveable jaw k. The said moveable jaw is hinged
to the holder at k² and is pressed upon the carbon i to retain it in position by a
spiral or equivalent spring passed around the two jaws. Figure 12 is a modifi-
cation wherein the spring is situated at the outer ends of the jaws. The carbon
may be readily withdrawn by simply pulling it from the holder and another may
be reinserted simply by holding open the moveable jaw and putting the carbon
in place after which on the said jaw being released the carbon is held firmly
in place.
Having now described and particularly ascertained the nature of my said
Invention and the manner in which the same is or may be used or carried into
effect I would observe in conclusion that what I consider to be novel and original
and therefore claim as the Invention secured to me by the hereinbefore in
part recited Letters Patent is:—
First In arc electric lamps providing the carbon holder rods or analogous
moving parts with a protecting stocking envelope or covering as hereinbefore
described with reference to the accompanying drawings.
Second-In arc electric lamps the combination of an airtight box or casing for
the regulating mechanism with the means for protecting the projecting rods or
parts claimed by the preceding claiming clause as hereinbefore described with
reference to the accompanying drawings.
Third In arc electric lamps the combination with an air tight box or casing
for protecting the regulating mechanism of the flexible coverings & through which
the said mechanism can be adjusted as hereinbefore described with reference to the
accompanying drawings.
Fourth-In arc electric lamps an air tight box or casing for protecting the
regulating mechanisin provided with a yielding or flexible bag or chamber h (or
several such chambers) for the purpose hereinbefore described and illustrated in the
accompanying drawings.
Fifth In arc electric lamps the holder consisting of a fixed jaw ja hinged
moveable jaw and a retaining spring as hereinbefore described and illustrated
in Figures 11 and 12 of the accompanying drawings.
In witness whereof I the said Percy Ruskin Allen have to this my Specification
set my hand and seal this twenty-first day of January One thousand eight
hundred and sighty thron
PERCY RUSKIN ALLEN (L.S.)