Improvements in Electric Arc Lamps.
Year: 1898

page_text: Improvements in Electric Arc Lamps.
ARTHUR JEFFERYS HILLS, Loughton Holme, Broadstairs, Kent, Electrical
Engineer, do hereby declare the nature of this invention to be as follows:
My invention relates to improvements in electric lamps of the arc type and has
for its object the simplification of the mechanism employed in controlling the arc
and consequently the reducing of the first cost. It also allows of single lamps
being employed on circuits of high voltage without the necessity for and conse-
quent loss of power caused by resistance coils or of reducing the number of lamps
to be run in series.
In lamps constructed in accordance with my invention I use two or more sets
of carbons which are electrically connected so as to be in series with one another.
Each set of carbon holders is independant of the other and is arranged to be
released lifted and retained by a clutch such as that used in some forms of the
well known brush" lamp and these clutches are so connected that they shall
operate simultaneously on all sets of carbon holders.
<<
A single electro-magnet or solenoid through which the whole of the current
passes controls these clutches and on the failure of the arcs or on the resistance
being increased owing to the lengthening of the arcs through the carbons being
burnt away all the carbon holders are released and the carbons drop into contact.
The magnet or solenoid will now pick up all the clutches and strike the arcs
in the usual well known manner.
'
By this means all the sets of carbons are adjusted and regulated by a single
electro magnet although their rates of burning away may be different owing to
inequalities of manufacture.
Owing to the carbons being in series the large waste of power through added
resistances or the necessity for unduly increasing the number of lamps is reduced
or entirely avoided and the cost of lighting is thereby lessened.
In some cases I prefer to use a thermal regulator to equalise the lengths of the
arcs between the different sets of carbons and an electro magnet or solenoid to
control the feeding of the carbons and the combined resistance of the arcs.
In this case the carbons would be fed simultaneously but would have a small
amount of motion relative to each other to make up for inequalities of burn-
ing and this motion would be controlled by the respective temperatures of their
thermal regulators.
In some cases it would be advantageous to allow the thermal regulators to alter
the relative positions of the lower carbons while the upper carbons are controlled
by the electro magnetic feed.
In some cases the shunt coils of the solenoids would be in two parts each part
being connected in series with one of the thermal regulators these combinations
being respectively connected in parallel with the several arcs.
The thermal regulators would consist of conductors one of which is connected
in parallel with each arc and whose temperatures and consequent lengths vary in
accordance with the resistances of the arcs.
Tin Caranth dow of January 1808

page_text: PREP
ARTHUR JEFFERYS HILLS, late of Loughton Holme, Broadstairs, Kent, but now
of 11, St. Lukes Close, Maidenhead, Berks, 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;
My invention relates to improvements in electric lamps of the arc type and has
for its object the simplification of the mechanism employed in controlling the arc
and consequently the reducing of the first cost.
It also allows of single lamps being employed on circuits of high voltage with-
out the necessity for and consequent loss of power caused by resistance coils or of
reducing the number of lamps to be run in series.
The following description shews one form of my invention as applied to an
are lamp of the class shewn in the drawings attached to this specification in which
Fig. 1 Sheet 1 shews a front view of an arc lamp and Fig. 2 Sheet 2 a side elevation
of the same partly in section and having certain parts omitted for the sake of
clearness.
Like letters in both figures indicate like parts.
The dotted lines represent the wires carrying the electric current.
A A is a cast iron frame or box to hold the controlling mechanism. In Fig. 2
it is shewn in section.
B1 B2 are the two rods to carry the upper carbons by means of the carbon
holders B5 B6.
C is the carrier for the lower carbons, one of its carbon holders being marked C³.
DD are the washers which act as clutches to lift the rods B₁ B2 when required.
E is the link by which these clutch washers are raised. The raising is effected
by the electro magnets or solenoids F1 F2 acting on their armature H with its
lever K to which the link E is connected.
L is a dash pot to control the speed of movement of the armature H.
A second electro magnet M is provided for a purpose to be explained hereafter.
Its armature consists of a lever N pivoted to the frame at one end, but insulated
from it.
This lever carries at its other end a contact screw O which when the lever is not
held up by the action of the magnet M, rests on the contact spring R and makes
electric connection between it and the frame A. The lever N with its contact
screw O and the contact spring R are not shewn in Fig. 2 and the magnet coil Fi
and the rod 33 are also omitted for the sake of clearness.
TT are the terminals to which the electric wires are attached.
133 & B4 are the upper carbons and C¹ & C³ the lower ones.
The carbon holders B & C are insulated from the carrying rods B³ & C.
The electric connections of the apparatus are as follows
The current enters the lamp at the terminal T¹.
It then passes round the coils F1 F2 of the large electro magnet or solenoid and
from there is led to the frame A & by the wire W to the carbon holder 135. It then
passes through the carbons B3 C₁ forming the first arc & on through the rod C &
wire W to the insulated carbon holder B.
Then through the second pair of carbons B+ C2 forming the second arc and
through the insulated carbon holder C³ and wire W2 to the magnet coil M & out
to the terminal T2.
A second or shunt connection leads from the terminal T¹ through the wire W³
lever N, contact screw O, spring R, to the frame, thus short circuiting the electro
magnet coils F1 F2 when the lever N is in its lowest position. The action of the
apparatus is as follows:

page_text: When the lamp is at rest & no current passing a connection exists through the
terminal T, wire W³, lever N, contact screw O, spring R, frame A, wire W &
through the carbon holders & carbons round the magnet M to the terminal T.
When the current is switched on, the magnet M raises the lever N & so breaks
the contact between O & R thus compelling the current to pass round the coils F1 F2
of the large electro magnet. This then raises the armature H & by means of the
lever K, link E & clutches D lifts the carbon rods B¹ B³ & so strikes both arcs
simultaneously.
The mechanism will now remain stationary until through the lengthening or
failure of the arcs the current is diminished to such an extent that the magnet M
lets the lever N fall & so short circuits the large magnet F1 F2. This in its turn
will let fall the armature H & releasing the clutches 1) D & allowing the carbons
to fall into contact when the whole operation will be repeated. In some cases I
dispense with the magnet M & its shunt circuit through N&R in which case the
current passes direct from the carbon holder C³ to the terminal T².
In some cases I use a thermal regulator to vary the relative lengths of the arcs.
The carbons are then fed simultaneously in any well known way, but those of
one set, either the two upper or the two lower are arranged to have a small amount
of motion relatively to each other so as to make up for inequalities of burning.
I control this motion by means of a thermal regulator consisting of 2 wires each
forming a shunt across one of the arcs and which are arranged by their expansion
or contraction to raise or lower the holder of the carbon in whose circuit they are.
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:-
In arc lamps in which two or more arcs are arranged in series the arrangement
of intermittent feed by which all the upper carbons are controlled by the one
mechanism but are able to fall independantly of each other through any distance
so as to come into contact with their respective lower carbons and to compensate
for any differences in the lengths of the arcs caused by unequal rates of burning.
Dated this 7th day of October 1898.
ARTHUR J. HILLS.