Improvements in Electric Arc Lamps.
Year: 1896

page_text: Improvements in Electric Arc Lamps.
I, FREDERIK VILHELM ANDERSEN, Electrical Engineer, of 14 Westdown
Road, Catford Bridge, in the County of Kent, do hereby declare the nature of
this invention to be as follows:-
This invention for improvements in electric are lamps relates to lamps of that
class in which the carbons tend to approach one another and in which the motion
is controlled by a brake.
In a lamp constructed according to this invention, the two carbons are connected
together by a flexible connection passing over a pulley fixed, together with a brake
pulley, on a spindle mounted in a lever frame preferably arranged horizontally
and pivotted at one end and normally resting on a stop at the other end. A strap
fixed to the lever frame or the lamp frame near the fulcrum of the lever frame
passes round the lower part of the brake pully and is connected to a lever the
position of which is regulated according to the resistance of the arc.
On passing a current to the lamp the regulating lever actuates the brake strap
and causes it to grip the brake pulley and then to raise it. As the pulley is fixed,
its periphery farthest away from the lever frame fulcrum is raised more than the
part nearer the fulcrum and causes the carbons to separate in a gentle and com-
paratively slow manner to strike the arc. As the length of the arc increases the
brake strap lowers and the lever frame comes on to its stop and any further
slackening of the brake strap releaves the pressure of the brake strap on its
pulley and allows the carbons to feed together in a regular and steady manner.
It will be seen that the brake strap lifts the carbons, the holders, travellers and
working parts of the lamp.
In an improved electro-magnetic arrangement constructed according to this
invention for regulating the position of the regulating lever, the core of a series
solenoid is suspended from one end of the lever and the core of a shunt solenoid is
suspended from the other end of the lever. The weight of the core of the shunt
solenoid can be adjusted so that the lamp can be used either as a differential
lamp or, by disconnecting the shunt coil from the lamp circuit, as a simple parallel
lamp.
In a duplex lanp the one regulating lever actuates both brake straps, the one
lever frame coming in contact with its stop slightly before the other and the
second set of carbons being connected to the series solenoid so that a less number
of turns shall be working as the solenoid is to exert a smaller pull.
In a modification of the duplex lamp, the second set of carbons is insulated until
the first pair has been consumed, when an automatic switch makes connection to
the second pair. In this case there is only one lever frame.
Dated this 29th day of June 1896.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.

page_text: Improvements in Electric Arc Lamps.
I, FREDERIK VILHELM ANDERSEN, Electrical Engineer, of 14 Westdown
Road, Catford Bridge, in the County of Kent, 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 :-
This invention for improvements in electric arc lamps relates to lamps of that
class in which the carbons tend to approach one another and in which the motion
is controlled by a brake.
In a lamp constructed according to this invention, the two carbons are connected
together by a flexible connection passing over a pulley fixed, together with a
brake pulley, on a spindle mounted on a lever frame preferably arranged hori-
zontally and pivotted at one end and normally resting on a stop at the other end.
A strap fixed to the lever frame or the lamp frame near the fulcrum of the lever
frame passes round the lower part of the brake pulley and is connected to a lever,
the position of which is regulated according to the resistance of the arc.
On passing a current to the lamp the regulating lever actuates the brake strap
and causes it to grip the brake pulley and then raise it. As the pulley is fixed, its
periphery furthest away from the lever frame fulcrum is raised more than the part
nearer the fulcrum and causes the carbons to separate in a gentle and comparatively
slow manner to strike the arc. As the length of the arc increases the brake strap
lowers and the lever frame comes on to its stop and any further slackening of the
brake strap relieves the pressure of the brake strap on its pulley and allows the
carbons to feed together in a regular and steady manner.
It will be seen that the brake strap lifts the carbons, the holders, travellers and
working parts of the lamp.
In an improved electro-magnetic arrangement constructed according to this
invention for regulating the position of the regulating lever, the core of a series
solenoid is suspended from one end of the lever and the core of a shunt solenoid is
suspended from the other end of the lever. The weight of the core of the shunt
solenoid can be adjusted so that the lamp can be used either as a differential lampor,
by disconnecting the shunt coil from the lamp circuit, as a simple series wound lamp.
In a duplex lamp the one regulating lever actuates both brake straps, the one.
lever frame coming in contact with its stop slightly before the other and the
second set of carbons being connected to the series solenoid so that a less number
of turns shall be working as the solenoid is to exert a smaller pull.
In a modification of the duplex lamp, the second set of carbons is insulated until
the first pair has been consumed, when an automatic switch makes connection to
the second pair. In this case there is only one lever frame..
In the accompanying two sheets of illustrative drawings,
Sheet 1 shows a simple lamp constructed according to this invention and Sheet 2
a duplex lamp.
Figs. 1 and 2 are sectional elevations at right angles to one another of the single
lamp and
Fig. 3 is a sectional plan showing the guides for the travellers.
Fig. 4 is a sectional plan of the brake lever and bracket.
Fig. 5 is a sectional plan showing the pivotted frame and brackets.
Figs. 6, 7 and 8 are detail views.
Figs. 9 and 10 are sectional elevations at right angles to one another of the
duplex lamp.
Fig. 11 is a sectional plan showing the bottom plate.
Fig. 12 is a sectional plan showing the top bracket lever dash-pot and front and
rear guides.

page_text: Fig. 13 is a sectional plan showing the controlling gear and
Figs. 14 and 15 are detail views.
Referring to Sheet 1 of the drawings:-The upper and lower carbon holders a b
are secured to rods a' b' sliding in guides a 2 b2 and connected together by a flexible
ccrd c passing over a pulley e fixed on an axle c2 on which is also mounted the
brake wheelf. The axle c2 is mounted in a lever frame d pivotted at one end d¹
to the pillars d 2 depending from the top plate e of the lamp. Normally the other
end of the frame d rests on a stop d 3 on one of the rods e 2 connecting together
the top and bottom plates ee of the lamp. A strap f¹ fixed at one end to the lever
frame d near its pivots passes round the lower part of the brake pulley fand is
attached at its other end to the lever g pivotted on lugs e 3 on the top plate e and
having suspended from its ends the cores gg2 of the series and shuut
solenoids g 3 g 4.
Normally the two carbons are in contact, with the lever frame d resting on its
stop d3. On passing a current to the lamp, the series solenoid 3 draws down its
core gl and raises the strap f' causing it first to grip the brake pulley f and hold
it firmly and then to raise it to separate the carbons and strike the arc. As the
length of the arc increases the brake strap flowers and the lever frame d comes
on its stop d 3 and any further slackening of the brake straps / relieves the
pressure of the brake strap on the pulley faud allows the carbons to feed together
in a regular and steady manner. It will be seen that the brake strap lifts the
carbons, the holders a 6 the traveller rods a' b' and lever frame d.
The lever g is connected to the cylinder h¹ of a dash pot whose piston his fixed
to one of the rods e 2.
Referring to Sheet 2, the mechanism of the duplex lamp is similar to that
described and is marked with similar letters of reference, but is in duplicate with
the exception of the lever g and solenoid cores and solenoids but the frame d of.
the pair of carbons to be first consumed is arranged to come on its stop d 3 slightly
before the other frame d comes on its stop. The dash pot h in the duplex lamp is
attached to the solenoid lever g and the piston h is attached to one of the rods e 2
as shown.
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 I
claim is :-
1. In an arc lamp in which the carbons tend to approach one another, a brake
pulley geared to or moving with a carbon, a pivotted frame supporting the brake
pulley, a stop for the frame to rest on, a brake strap passing round the pulley and
having one end fixed, and a means for determining the position of the other end
of the strap according to the resistance of the arc.
2. In an arc lamp in which the two carbons are connected together by a cord
passing over a pulley and in which the carbons tend to approach, a brake pulley
mounted on the axle of the cord pulley, a pivotted frame carrying the two pulleys,
a stop for the frame to rest on, a brake strap passing round the brake pulley and
having one end fixed and a means for determining the position of the other end of
the strap according to the resistance of the arc.
3. The single are lamp substantially as described with reference to Sheet 1 of the
drawings.
4. The duplex arc lamp substantially as described with reference to the
drawings.
5. An arc lamp constructed and working substantially as described with reference
to the drawings.
Dated this 29th day of March 1897.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.