Improvements in Electric Arc Lamps.
Year: 1891

page_text: Date of Application, 21st Nov., 1891
Complete Specification Left, 20th Aug., 1892-Accepted, 24th Sept., 1892
PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lamps.
1, JOHN HALL RIDER, Northern Telegraph Works, Halifax, Electrical
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in electric are lamps and more particularly
those which are regulated or controlled by means of main circuit and shunt
solenoids or electro magnets acting upon a rocking frame or lever, the movements
of which are transmitted to a brake, clutch, or similar device.
It is customary in such lamps to fix the cores of the regulating solenoids
to the extremities of the rocking lever and it is necessary that one end of
the rocking lever should be so weighted as to cause it to fall and release the.
clutch or brake device when the current is stopped. It follows therefore that
the main circuit solenoid must be made more powerful than the shunt as it has to
lift the weighted end of the rocking frame to start the arc and maintain it in
position against the pull of the shunt solenoid, which increases in force with, the
length of the arc. Any variation in the main current strength will therefore
affect the regulation of the lamp much more readily than a variation in, the
strength of. the shunt solenoid. This is undesirable as it makes the proper burning.
of the lamp and the length of the are depend to a large extent upon the current
being maintained at a constant value.
In a lamp constructed in accordance with this invention however the shunt
solenoid can be made more powerful than the series or main circuit solenoid, and
thus the regulation of the lamp is less affected by variations in the main current
strength and more directly controlled by the shunt solenoid.
In carrying out this invention I take any arc lamp having a rocking frame with
series and shunt solenoids or electro-magnets at its ends and I weight the one end
so that it falls and releases the clutch or brake mechanism when the current is
stopped. 1.also arrange another weight so that it is applied to the opposite end
of the rocking lever when the current is on and there balances or overbalances the
said rocking lever and relieves the series solenoid of the work of supporting it. The
series solenoid need therefore only be powerful enough to raise the rocking lever
and pull the are when the current is first turned on, the shunt solenoid not having
any power until the arc is pulled. The weight being thus practically transferred
to the other end of the rocking lever the shunt solenoid is enabled to play a much
more important part in the regulation and can be made more powerful than the
series. It is necessary that this second weight be taken from the rocking frame
when the current is stopped in order to allow the clutch or brake device to
disengage and the carbons to come together.
This accomplish in the following manner. When the regulating coils are
mounted above the rocking frame, the series at the one end and the shunt at the
other with their cores attached to the end of the rocking frame, I allow the core of
the shunt solenoid to slightly project below the level of the rocking frame and 1
support an iron weight directly underneath the end of the said core in such a
position that when the series end of the rocking frame is lifted up and the arc.
pulled the said iron weight attaches itself by magnetic attraction to the end of the
shunt core and continues so attached as long as the current is maintained and no
longer, when it immediately falls. When the regulating coils and their cores are
so arranged that the series end of the rocking frame is pulled down to strike the
arc I arrange, the iron weight in a similar manner but so that it attaches itself to
the core of the series solenoid. In any case 1 so place the iron weight that when

page_text: the arc is pulled it attaches itself to the system in such a manner as to help in
maintaining the separation of the carbons.
Dated this 90th day of November 1801
JOHN H. RIDER.
COMPLETE SPECIFICATION.
Improvements in Electric Arc Lamps.
I JOHN HALL RIDER Northern Telegraph Works Halifax 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:-
This invention relates to improvements in electric are lamps and more particularly
those which are regulated or controlled by means of main circuit and shunt
solenoids or electro magnets acting upon a rocking frame or lever the movements
of which are transmitted to a brake clutch or similar device.
It is customary in such lamps to fix the cores of the regulating solenoids to the
extremities of the rocking frame and it is necessary that one end of the rocking
frame should be so weighted as to cause it to fall and release the clutch or brake
device when the current is stopped. It follows therefore that the main circuit
solenoid must be made more powerful than the shunt as it has to lift the weighted
end of the rocking frame to start the are and has also to maintain it in position
against the pull of the shunt solenoid which increases in force with the length of the
Any variation in the main current strength will therefore affect the regulation
of the lamp much more readily than a variation in the strength of the shunt solenoid.
This is, undesirable as it makes the proper burning of the lamp and the length
of the arc depend to a large extent upon the current being maintained at a
constant value.
arc.
In a lamp constructed in accordance with this invention however the shunt
solenoid can be made more powerful than the series or main circuit solenoid and
thus the regulation of the lamp is less affected by variations in the main current
strength and is more directly controlled by the shunt solenoid.
In carrying out this invention 1 take any arc lamp having a rocking frame or
lever with series and shunt solenoids or electro magnets at its ends and I weight
the one end of the rocking frame so that it falls and releases the clutch or brake
mechanism when the current is stopped. I also arrange another weight so that it is
applied to the opposite end of the rocking frame when the current is on and the
are pulled and which weight then tends to balance or overbalance the said rocking
frame and to relieve the series solenoid of all or part of the work of supporting it.
The series solenoid need therefore only be powerful enough to raise the rocking
frame and pull the are when the current is first put on, the shunt solenoid not
having any power until the arc is pulled.
The weight being thus practically transferred to the other end of the rocking
frame the shunt solenoid is enabled to play a much more important part in the
regulation and can be made more powerful than the series. It is necessary that
this second weight be taken from the rocking frame when the current is stopped
in order that the clutch or brake device may disengage and the carbons come
together.
This accomplish in the following manner. When the regulating coils are
mounted above the rocking frame the series at one end and the shunt at the other
with their cores attached to the ends of the rocking frame I allow the core of the
shunt solenoid to project below the level of the rocking frame and I support an
iron weight directly underneath the end of the said core in such a position that
when the series end of the rocking frame is lifted up and the arc pulled the said
iron weight attaches itself by magnetic attraction to the end of the shunt core and

page_text: continues so attached as long as the current is maintained and no longer when the
core immediately falls.
Figures 1 and 2 of the accompanying drawings show this invention applied to
the motion of an arc lamp where the coils are mounted above the rocking frame.
The corresponding parts in these and the remaining figures are lettered similarly.
A and B are respectively the series and shunt solenoids and A' and B' are their
cores which are attached to the rocking frame C pirotted at D. The bearing D
is fixed to any convenient part E of the framework of the lamp. The fixed
weight W which may be of any form shape or construction causes the series end
of the rocking frame C to be at its lowest point and the clutch or brake device to
be disengaged when the current is off. This position is shewn in Fig. 1. Fig. 2
shews the position of the rocking frame when the current has been applied and
the iron weight W₁ has attached itself to the core B¹ of the shunt solenoid B by
means of magnetic attraction.
Figs. 3 and 4 shew a modification of this invention where the shunt core B' does
not project below the end of the rocking frame but is made somewhat shorter and
is connected to the rocking frame by means of the tube F. In this case the iron
weight W is made to enter the tube F, which may thus serve as a guide.
Fig. 3 shows the positions when the current is off and Fig. 4 the positions when
the current has been applied and the weight W' has attached itself to the shunt
core B¹
This modification enables the arc to be pulled more easily as the
shunt core B' being shortened and lying more nearly in the centre of the shunt
solenoid B is not so strongly controlled by any current in the shunt solenoid.
Directly however the iron weight W₁ has attached itself to the shunt core it acts
as a prolongation of that core and is immediately held in control by the shunt
solenoid.
Figs. 5 and 6 show this invention applied to the motion of an arc lamp where
the coils are mounted below the rocking frame. In this case the fixed weight W
is applied to the shunt side of the rocking frame C and the iron weight W' is held
underneath the core A¹ of the series solenoid A. Fig. 5 shows the positions when
the current is off and Fig. 6 the positions when the current has been applied and
the weight W has attached itself to the end of the series core A¹.
Figs. 7 and 8 show this invention applied to the motion of an arc lamp where
the coils are mounted one above the other the series coil A being at the bottom
5 and the shunt coil B being at the top.
The cores A and B are then generally continuous and in one length. In this case
the fixed weight W is placed at the opposite end of the rocking frame C and when
the current is off as in Fig. 7 it overbalances the system and takes the lowest point.
When the current has been applied the series coil A pulls down its end of the
rocking frame and the weight Wattaches itself to the core A as shewn in Fig. 8.
The weight W need not be formed entirely of iron. It may be partly of iron
and partly of any other substance as in Figs. 5 and 6 where the iron part is shewn
at G above the weight and connected to it by means of a rod H.
When the current is off the weight W rests on the base of the lamp or on any
convenient part. This support is not shown in the drawings.
Any efficient device may be used to control the motion of the carbons provided
it is capable of being connected to and controlled by the rocking frame or lever.
I need not use the exact forms or positions. of rocking frame coils cores or
weights as indicated in the various figures but in any case I so place the iron
weight that when the arc is pulled it attaches itself to the system in such a manner
as to help in maintaining the separation of the carbons.
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:
1st. In electric arc lamps which have the movements of the carbons controlled
by main circuit and shunt windings acting upon iron cores attached to a rocking

page_text: frame making the shunt.core of such arlength and so connecting it to the rocking
frame that it occupies an approximately central position with regard to the shunt
solenoid, and arranging an iron weight so that it becomes attached to and acts as a
prolongation of the said shunt core when the arc is pulled, substantially as described
and illustrated in Figs. 3 and 4 of the accompanying drawings.
2nd. In electric.arc lamps which have the movements of the carbons controlled
by main circuit and shunt windings acting upon iron cores attached to a rocking,
frame arranging a weight: in such a manner that it attaches itself by magnetic
attraction to one or other of the cores when the current is on so as to help in
maintaining the separation of the carbons substantially as described and illustrated
in the accompanying drawings.
Dated this Nineteenth day of August 1899