Year: 1898

page_text: We, ROOKES EVELYN BELL CROMPTON and EDMUND ARTHUR NORMAN POCHIN,
both of Arc Works, Chelmsford, in the County of Essex, Electrical Engineers,
do hereby declare the nature of this invention to be as follows:-
Our improvements consist in so arranging the parts of are lamps that one and
the same lamp can serve several purposes, i.e. that of a continuous current open
lamp, an alternating current open lamp, a continuous current enclosed arc lamp,
an alternating current enclosed arc lamp.
Our improvements have for their object the simplification and cheapening of
the manufacture of these lamps and also to give greater facilities for putting in
new carbons, attaching the air tight enclosure, raising and lowering the protect-
ing globe or lantern and the maintaining of the carbons duly in line.
The essential features of our new arc lamps are the following and consist of a
base plate having one or more flanges and 4 vertical tubes attached to it the posi-
tion of these tubes when seen in plan view is preferably 90 degrees apart, two of
them passing right through the base plate, and other two do not. These tubes
accordingly form a guide or a support for the lower portion of the lamp as well
as 4 pedestals above the base plate which serve to support the mechanism.
Through the base plate there also passes approximately in a central position a
vertical metal tube which contains the carbon with its holder and spring contact
similar to that described in the Specification of our Letters Patent No. 6276 dated
March 10th 1897. At the bottom of this tube we prefer to attach the clutch or
feeding device and at the top of it we secure the piston or plunger of the dash pot
at which near the centre of this tube we fix a cross piece to which the core or
cores which are affected by the magnets are attached by means of buffer springs.
When our lamp is intended for alternating current this core consists preferably
of U-shaped iron stampings rivetted together but in such manner that a space
can be left in the centre of the bend of the U to allow the central tube to pass
through it. The two legs of this core enter two vertical solenoids each supported
on two of the 4 upright pedestals above referred to, these solenoids are provided
with the usual winding.
The 4 tubes are braced together at their upper ends by suitable castings which
also serve to support the dash pot, and a prolongation of them also serves to sup-
port a choking coil, transformer, resistance or other equivalent device which may
be found necessary in practice to control and regulate the lamp, these tubes also
serve to hold the outside cover of the lamp, the pair of tubes which extend down-
wards from the base support at their lower ends an insulated cross piece which
carries the inner or are enclosing globe, preferably by means of a gland or
stuffing box provided with packing of a suitable material such as is commonly
used where a tight joint is required and where the temperature is somewhat high.
Into this cross piece is screwed the lower carbon holder, the form which we prefer
for this consists of a split tube having a thread cut upon its outer surface, a

page_text: portion of this thread is screwed into a threaded cap which contains mica washers
and to this also we are able to secure an insulated head screw which serves to
hold the outer globe in position, this outer globe is attached to a tapped stud
connected with a cross piece and two upright rods which pass telescopically within
the pair of lower tubes and so allow the outer globe to be raised and lowered by
these rods sliding up and down within the tubes.
The inner globe is fitted with an air excluding cap through which the upper
carbon passes, this cap also serves as a fixed point on which the finger of a cam
shaped pivotting piece can rest, whenever it is desired that the clutch should come
into action and the carbon be fed downwards through the tube.
Dated the 16th day of December 1898.
Improvements in Electric Arc Lamps.
We, ROOKES EVELYN BELL CROMPTON and EDMUND ARTHUR NORMAN POCHIN,
both of Arc Works, Chelmsford, in the County of Essex, Electrical Engineers,
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 fol-
lowing statement:-
Our improvements consist in so arranging the parts of arc lamps that one and
the same lamp serve for several purposes i.e. that of a continuous or alternating
current un-enclosed lamp or as a continuous or alternating current enclosed lamp.
They have for their object the cheapening of the manufacture of these lamps,
increasing the facilities for putting in new carbons, for attaching the air tight
enclosure, for raising or lowering the protecting globe or lantern and for the
maintaining of the carbons duly in line.
Fig. 1 is a side sectional elevation of our improved lamp with the outer globe
raised and in working position. Figure 2 shows the same in plan view and
Figure 3 shows the same lamp with the outer globe lowered but with the enclosure
in position.
The
The base plate a is provided with one or more flanges and four vertical tubes c.
The position of these tubes when seen in plan view is preferably 90 degrees apart.
Two of them pass right through the base plate, the other two do not.
tubes which pass through the base plate form a guide or support for the lower
portion of the lamp the upper ends of the same and of the two shorter tubes
serve as four pedestals to support and firmly brace the mechanism together. The
vertical tube which contains the carbon e passes through the base plate in an
approximately central position. The upper end of the top carbon fits into a spring
carbon holder (f indicating the spring contact) similar to that described in the
Specification of Letters Patent No. 6276 of 1897 granted to us and shown at n,
Figs. 1, 2 and 3 of that specification. At the bottom end of the vertical tube
we prefer to attach our clutch or feeding device g. j is an ash pan. is a cross-
piece. At or near the centre of the tube we fix the core, or cores which are
actuated by the solenoids o, o, as shown. m, m are buffer springs and n magnets.
When our lamp is intended for use with alternating currents the core consists
preferably of U shaped iron stampings rivetted together, but in such a manner
that a space is left in the centre of the bend of the U to enable the central tube d
to pass through it.
The two legs of this horse-shoe shaped core enter the two vertical solenoids o o

page_text: which are supported on two of the upright pedestal tubes. These solenoids are
provided with the usual winding. The four tubes cc are braced together at their
upper ends by suitable castings which also serve to support the dash pot ga
prolongation of them also serves to support the choking coil, transformer, resist-
ance or other equivalent device which is found necessary in practice to control
and regulate the lamp. These tubes also serve to hold the outside cover of the
lamp. The pair of tubes which pass downwards from the base of the support, at
their lower ends have an insulated cross pieces which carries the inner or are
enclosing globe t preferably by means of a stuffing box provided with packing of a
suitable nature that is to say where a somewhat tight joint is required where the
temperature is high.
Into this cross piece we screw the lower carbon holder in the form of a split tube
having a thread cut upon its outer surface. A portion of this thread is screwed
into the threaded cap w containing mica washers. To this also we attach an insu-
lated screw head, which serves to hold the outer globe in position and this outer
globe is attached to a tapped stud y connected to a cross piece z and two upright
rods 2 and 22 which pass telescopically within the pair of lower tubes.
The cap of the inner globe has a fixed point on which the finger of a feeding
clutch piece can rest whenever it is desired that the clutch should come into action
and the carbons be allowed to feed downwards through the tube.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is:-
-
1. An arc lamp frame consisting of a base plate carrying four tubes two long
ones and two short ones the longer pair being disposed at right angles to the
shorter pair the prolongation of the upper ends of these tubes carrying the internal
resistance, transformer, choking coil or similar extra device, the lower ends acting
as guides for the outer globe supports.
2. In arc lamps the use of a lower carbon holder consisting of a threaded split
tube combined with a cap containing insulated washers and which also holds the
outer globe in position.
3. In arc lamps the arrangement and combination of parts, substantially as
herein described and set forth in the drawings attached hereto.
Dated the 16th day of September 1899.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, W.C., Agents for the Applicants.