Improvements in Electric Arc Lamps.
Year: 1897

page_text: Date of Application, 7th Jan., 1897.
Complete Specification Left, 3rd Feb., 1897-Accepted, 10th Apr., 1897
Improvements in Electric Arc Lamps.
1
I, ALFRED GEORGE STOCKWELL of 46 Delafield Road'Old Charlton in the County
of Kent Electrician do hereby declare the nature of this invention to be as
follows:
"
My invention relates to improvements in construction and brake, mechanism in
electric arc lamps. Referring to the accompanying. drawings according to, this
invention I build up the framework of the lamp in the usual way,; with a disc A..!
which I call the groundplate, having a centre socket B into which is fixed the centre
tube C of the lamp.. At the top of this tube is fixed a square frame D within which
the brake and drawúp wheels E. F. F' work between centres.
In the centre tube and at right angles to this frame, I fix permanently. two
pins G. G at a given distance apart, on these pins the main and shunt coils are
supported and secured with nuts, above these coils I pivot a rocking bar H, to
which is suspended the soft iron cores by the brass;stems J. J' and also the links K. K
connected to the locking lever of the brakewheel mechanism.
-
In most cases hitherto the means used for clutching the wheel and brake mechanism
are eccentric which seriously affects the feed of the lamp. I therefore fork all the
levers and links connected with the brake mechanism and the whole is lifted
concentrically.
The brakewheel E.is fixed on the centre of a spindle and is lineable with the"
rocking bar, it is simply a plain wheel with a smooth edge and sides and revolves
freely between the arms of weighted quadrant plates M. M. The brakeband is
made of oblong plates riveted together in pairs, each rivet carrying a distance
piece N curved to the radius of the wheel and a little wider than the edge, so as;,,
to allow the wheel to pass freely between the plates. One pair of these plates O are
extended on one edge to take a third rivet which holds a skid P with a crosspiece to
which is attached a spiral spring Q on either side of the wheel and connected through
the rentre to the quadrant arms, or with a crank carrying a counterweight as in Fig. 5
to give the necessary tension to the skid to prevent overfeeding of the lamp without
the use of india rubber silk cord or other perishable or clogging materials.
Between the quadrant plates I pivot two forked. levers, one on the horizontal line
and one below, the first named being the tripping lever S the lower one being the,
locking lever L to which the ends of the brakeband are connected, and in such a
position that the upward motion of the rocking bar H gives a double purchase to the
brakeband and the wheel is clutched by the curved distance pieces, this lever has also
a raised 'tailpiece R for fine adjustment with the tripping lever.
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The tripping lever is much longer than the locking, lever and comes nearer they
centre of the frame, and is pivoted at the other extreme end, as shewn in Fig. 4 and...
has a block, at a given angle through which a screw T passes which is locked by a
small nut-when finally adjusted. A forked braketable U is permanently fixed to the
square frame in such a position that the prongs of the tripping lever rests upon it on.
the downward or return motion of the rocking bar, directly this takes place the fine
adjustment screw T at the other end trips up the tailpiece R of the locking lever so
that the grip on the brakewheel is released. the skid P coming into action gives a slow"
niform faad to the lawn
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page_text: The focussing or drawup wheels F. F' are fixed one on either end of the spindle
carrying the brake wheel, the positive wheel F¹ being fixed direct on to the spindle,
the negative wheel F being insulated from the spindle, each wheel being connected
to their respective drawups with a flexible metallic tape or cord. I thus use three
wheels in this system.
For the lower structure of the lamp I use two pillars V. V₁ fixed in the ground-
plate and having a light crossbar W at their lower ends, the negative drawup passes
through an insulated hole lineable with the pillars having a guide fork fixed to it
with insulated rubbers X to slide up and down the near pillar keeping the carbon
in a central position in its up and down movements.
The positive drawup is a tube Y which slides over a rod Y' fixed in the crossbar,
and which extends a considerable distance through the groundplate A so as to give
a good direction to the said tube in all positions, to the lower end of this tube
I fix a weighted clip Z which carries the positive carbon holder, and is forked at
one end so that at the same time it acts as a guide to keep the carbon central in
its up and down movements, to the top of each drawup I fix a suitable connector
for attachment to their respective focussing wheels.
Dated this Seventh day of January 1897
I ALFRED GEORGE STOCKWELL of 46 Delafield Road Old Charlton in the County
of Kent, Electrician, 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 improvements in construction and brake mechanism in
electric arc lamps.
Referring to the drawings "filed with my Provisional Specification
"
Fig. 1 and 2 are elevations at right angles to each other of the framework of an
electric are lamp according to my invention.
Fig. 3 is a plan of the brake mechanism and focussing wheels.
Fig. 4 is a side elevation shewing the respective positions of quadrant, brakeband,
skid, locking and tripping levers.
Fig. 5 is also a side elevation of the brakewheel shewing counter weight giving
tension to skid in lieu of springs.
Fig. 6 is a plan of groundplate shewing rocking bar and positions of negative and
positive drawups.
According to this invention I build up the framework of the lamp in the usual way,
with a disc A having a centre socket B into which is fixed the centre tube of the
lamp At the top of this tube is fixed a square frame D. within which the brake
and drawup wheels E. and F. F' work between centres.
In the centre tube and at right angles to this frame I fix permanently two pins G. G
at a given distance apart, on these pins the main and shunt coils are supported and
secured with nuts, above these coils I pivot a rocking bar H to which are suspended
the cores by brass stems J. J' and also the links K. K. connected to the locking lever I
of the brakewheel mechanism.
In most cases hitherto the means used for clutching the wheel and brake mechanism
are eccentric which seriously affects the feed of the lamp, I therefore fork all
the levers and links connected with the brake mechanism and the whole is lifted
concentrically.

page_text: The brake wheel E is fixed on the centre of a spindle and is lineable with the
rocking bar, it is simply a plain wheel with a smooth edge and sides and revolves.
freely between the arms of weighted quadrant plates M. M'.
The brakeband is made of oblong plates riveted together in pairs each rivet carrying
a distance piece N. curved to the radius of the wheel and a little wider than the edge..
so as to allow the wheel to pass freely between the plates, one pair of these plates O
are extended on one edge to take a third rivet which holds a skid P. with a crosspiece
to which is attached a spiral spring Q on either side of the wheel and connected,
through the centre to the quadrant arms or with a hooked lever or crank carrying a.
counterweight as in Fig. 5 to give the necessary tension to the skid to prevent
overfeeding of the lamp without the use of indiarubber, silk cord, or other perishable
or clogging material.
Between the quadrant plates I pivot two forked levers, one on the horizontal line.
and one below, the first named being the tripping lever S the lower one being the-
locking lever L to which the ends of the brakeband are connected and in such a
position that the upward motion of the rocking bar H gives a double purchase to the-
brakeband and the wheel is clutched by the curved distance pieces, this lever has also
a raised tailpiece R for fine adjustment with the tripping lever.
The tripping lever is much longer than the locking lever and comes, nearer the
centre of the frame and is pivoted at the other extreme end "as shewn in Fig. 4" and
has a block at a given angle through which a screw T passes which is locked by a
small nut when finally adjusted. A forked braketable U is permanently fixed to the -
square frame and in such a position that the prongs of the tripping lever rests upon
it on the downward or return motion of the rocking bar, directly this takes place the
fine adjustment screw T at the other end trips up the tailpiece R of the locking lever
so that the grip on the wheel is released, the skid P coming into action gives a slow
and uniform feed to the lamp.
The focussing or drawup wheels F. F' are fixed one on either end of the spindle.
carrying the brake wheel, the positive wheel F' being fixed direct on to the spindle,
the negative wheel F. being insulated from the spindle, each wheel being connected to...
their respective drawups with a flexible metallic tape or cord, I thus use three wheels.
in this system.
For the lower structure of the lamp I use two pillars V. V₁ fixed in the groundplate
and having a light crossbar W at their lower ends, the negative drawup passes-
through an insulated hole lineable with the pillars having a guide fork fixed to it with
insulated rubbers X to slide up and down the near pillar keeping the carbon in a.
central position in its up and down movements.
The positive drawup is a tube Y which slides over a rod Y' fixed in the crossbar
and which extends a considerable distance through the groundplate A so as to give.
a good direction to the said tube in all positions, to the lower end of this tube I
fix a weighted clip Z which carries the positive carbon holder and is forked at one
end so that it at the same time acts as a guide to keep the carbon central in its-
up and down movements, to the top of each drawup I fix a suitable connector for
attaching to their respective focussing wheels.
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 L
claim is-
1st. In the construction of an electric arc lamp; a series of wheels revolving
between centres in a square frame, the supporting of the coils on fixed pins or bolts-
& secured with nuts, and the arrangement of the drawups, substantially described
with reference to Figs. 1 and 2 of the accompanying drawings.
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2nd. In the brake mechanism of an electric are lamp; a brakeband made with..
oblong plates and curved distance pieces for clutching the wheel, with skid attach-
ment having tension applied by springs or weight, substantially as described with.
reference to Figs. 3, 4 and 5 of the accompanying drawings.
3rd. The combination of forked locking and tripping levers L. R. and S with.

page_text: fine adjustment, screw T. pivoted between¯quadrant plates and connected-to-the-
said brakeband, substantially as described with reference to Fig. 4. of the accompanying
drawings.
Dated this 2nd day of February 1897