IMPROVEMENTS IN ELECTRIC LAMPS
Year: 1881

page_text: LETTERS PATENT to Andrew Ainslie Common and Henry Francis Joel, both
of 52, Queen Victoria Street, in the City of London, Electric Light Engineers,
for an Invention of "IMPROVEMENTS IN ELECTRIC LAMPS."
PROVISIONAL SPECIFICATION left by the said Andrew Ainslie Common
and Henry Francis Joel at the Office of the Commissioners of Patents on the
10th March 1881.
ANDREW AINSLIE COMMON and HENRY FRANCIS JOEL, both of 52, Queen
Victoria Street, in the City of London, Electric Light Engineers. "IMPROVEMENTS
IN ELECTRIC LAMPS."
This Invention relates to improvements in electric lamps or regulators of the
arc and incandescent systems. With a view to simplifying the construction of arc
lamps, reducing the number of moving parts, and dispensing with the use of delicate
springs and clockwork, we propose to apply the comparatively large movement of
an iron core in a solenoid, with or without a shunt, to give the trifling necessary
movement to the carbons or electrodes of the lamp by a jointed lever, or its equivalent,
in such a way as to form, feed, and regulate the arc in a simpler manner than
heretofore.
According to one arrangement we fix on a suitable frame forming a portion of
the lamp, and through which slides the upper carbon holder, a metallic disc and
pinion gearing into the rack portion of the above holder. On the edge of the disc
a suitable flange is provided, to which is fitted a gripping lever of the kind known
as the "silent feed," this lever being attached at the other extremity to the core.
In the normal state of the lamp the carbons are in contact and the gripping
lever at its lowest point and free from the disc. Immediately a current is sent
through the lamp the iron core rises in the solenoid, lifting the lever and gripping
the disc, thus forming a continuous lever to lift the upper carbon and holder and
form the arc. When the are becomes too long and the current weakens the core
falls with the lever, releasing the disc and allowing the top carbon to approach the
lower one; or in the place of the disc and pinion in the above example a round
or other shaped carbon holder not racked can be gripped by two jaws worked by

page_text: a gripping lever in a similar manner to the same end. The movement of the
gripping lever in releasing itself from the disc can be obtained by a suitable
tripping piece placed so as to act before the core has quite fallen, or at any desired
point. We also propose to apply a standard or controlling lamp, so arranged that
if placed in circuit with other lamps these lamps will be regulated and controlled
by the action of the standard lamp, thus simplifying the construction of these other
lamps.
For incandescent electric lamps we propose the following improvements on the
Letters Patent granted to Henry Francis Joel, No. 5157/79
In an incandescent lamp in which the bottom electrode is kept in contact with
the top electrode by means of weights or springs we arrange an electro-magnet, or
its electrical equivalent, in a shunted circuit, so that if by any mischance the smaller
moveable electrode should stick in its contact jaws or its point become broken off,
and an arc formed by either means, the electro magnet would come into action &
free the contact jaws of the smaller electrode from lateral pressure and restore the
normal condition of working. We also make provision for replacing the smaller
electrode by making the stem of the lamp to open in halves on hinges, each part
forming part of the electrical circuit. We also employ a method of fastening these
sides of the lamp by means of a button or knob arranged in such a way that when
opening the lamp for any purpose the lamp becomes for the time short circuited.
We also propose to use a flexible wire suspension in connection with a hanging
incandescent lamp in such a way that the means of suspension always forms part
of the circuit; also as an improvement in the lateral contact or jaws of the moveable
electrode we employ a thin lateral extension of the jaw firmly attached to the.
upper frame.
We also construct the lamps by forming the halves of the stems of a
semicircular section with the addition of a beaded extension of the edge, so as to
form a hinge on one side and a passage for an insulated wire forming part of the
circuit on the other. We also employ an arrangement of a small opal or obscured
glass globe or shade placed close to and surrounding the light in combination with
a larger slightly obscured or clear glass globe or shade outside.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Andrew Ainslie Common and Henry Francis Joel in the Great Seal
Patent Office on the 10th September 1881.
ANDREW AINSLIE COMMON and HENRY FRANCIS JOEL, both of 52, Queen
Victoria Street, in the City of London, Electric Light Engineers. "IMPROVEMENTS
IN ELECTRIC LAMPS."
Our said Invention relates to certain improvements in electric light are lamps
or regulators, and also to improvements in the construction of incandescent electric
light lamps.
The improvements in electric light arc lamps or regulators consist essentially of
a simple device and apparatus for striking and controlling the arc actuated by a
solenoid, also of various devices for feeding and regulating the length of arc, also
of improvements in the mechanical construction of the incandescent lamps described
in the Letters Patent granted to Henry Francis Joel, No. 5157, A.D. 1879, whereby
the action of such lamps is rendered more certain, and they are better adapted
for practical use by inexperienced persons.
And in order that our said Invention may be fully understood we shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the explanatory Sheets of Drawings hereunto annexed, the
same letters of reference indicating corresponding parts in all the corresponding
Figures.
Figures 1 to 9, Sheet 1, of our Drawings show the various forms of electric arc
lamps containing the before mentioned improvements. Figure 1 shows a sectional
elevation of a complete lamp, and Figure 2 a plan of same. In the box or frame A
is mounted on bearings B a pinion P and large disc or wheel D; into the pinion P
is geared the rack R, to which rack the top electrode E is attached; on the other
end of the rack R is a piston head P which almost fits into a cylinder P¹, the said
cylinder P¹ being filled with glycerine or other fluid. As the rack R falls the
glycerine must pass through the orifices shown by dotted lines in P, and so retard
and regulate the fall of R, as described in the Specification to Letters Patent
granted to Andrew Ainslie Common, No. 368, A.D. 1870. On the axis of P are
attached two weighted arms W, between which arms a gripping lever L is pivotted
at 7; the said arms W rest upon the adjustable support S. On the other side of
the box is an electro magnet solenoid coil M, one part or section being wound with
thick wire in the main circuit, the other part being wound with fine wire of
suitable resistance and in reverse direction to the thick wire and connected to
shunt across the arc as is well understood. In the centre of this coil is an iron
core C, the bottom end of this core C being connected loosely to the end of the
gripping lever L. At the bottom of the lamp is shown the globe G, the lower
electrode E', the frames' A', A2, A3, and the globe holder G₁, with an arrange-
ment g, g, for lowering the globe. The action of this lamp is as follows:-When
an electric current is sent through the thick wire coil of M it passes through the
carbons E and E¹ and back to its source, the core C is sucked or drawn into the
coil M and raises the lower end of the lever L, causing the other end to move on
the pivot l, grip the disc D at the point, and turn the pinion P, this raises the
rack R with the top carbon E attached and so strikes the arc. When the arc
becomes too long the action of the thick wire coil on M is weakened and the shunt
coil strengthened, the core C drops again, releasing the gripping lever L from D and
allowing the rack R to fall; the above action is then repeated, and so on until all
the carbon is consumed. The disc D may be milled on its edge if desired, and two
sets of gear with two carbons may be used, as shown in plan, Figure 2, or two

page_text: electro magnetic solenoids arranged side by side, the essential features in this
lamp being the transferring the large movement of the solenoid core to a fine
movement of the carbon by means of the disc and gripping lever regulated by the
current and feeding the carbon down as required.
Figure 3 shows a slight modification of this lamp, in which two coils m, m, are
combined with one double core C, the two sets of discs D and gripping levers L
shown being arranged as before described. In this arrangement a forward or
preceding movement is given to one of the gripping levers L so that it may grip
before the other, as shown in dotted lines, Figure 1, and lift its carbon first; in this
case the last lifted carbon strikes the arc, and by preference continues to burn
until entirely consumed, when the other takes up the light and is in turn consumed,
thus forming an automatic double lamp.
Figure 4 shows a sectional view of part of a similar lamp, but with two
clamps H, H', gripping a rod E, the adjustments being obtained by the screws S, S',
the action and other parts being similar to the lamp shown in Figure 1; Figure 5
shows an additional device for giving a more delicate feed than that of the lamp in
Figure 1. In this lamp (Figure 5) an adjustable spring K is fitted to the end of
the lever L under the pivot and is so adjusted that the moment the grip of L is
off at , the spring K comes into contact with the rim of D, and so controls the
fall of R; the more L falls the greater the pressure upon the rim of D, and the
greater the control; Figure 6 also shows another modification of Figure 1. In this
modification (Figure 6) is shown the tripping bell cranked lever T, which is so
arranged that the arm W rests by means of a pin w upon the top of the vertical
arm of T; any additional fall of the lever L causes the projection at its end under
the pivot to press against the vertical arm T and push it away, thus releasing W
and momentarily restoring the gripping lever L to its former position. This
double movement allows the feed to take place when the core has fallen only a part
of its way, and where the balance of the two coils of wire on the electro magnet M
upon the core C is nearly even, and thus the feeding action is more sensitive,
whilst the tripping lever T provides that the full action may be obtained when
starting.
Figure 7 shows a simple and efficient form of gripping levers L. The disc D has
its rim T shaped, and the end of the gripping lever L is made to embrace it on
both sides; in the position shown the lever L rests upon the screw S and the disc D
is free, the rack could therefore fall. A slight upward movement of the lever L at
the end by C would cause the head H to bind upon the two sides of the rim of D,
and turn D lifting the rack, as in the herein before described lamps; Figures 8
and 9 show a sectional elevation and plan of a lamp with an arrangement of wheel
gearing to regulate the rise and fall of the rack R and carbon attached thereto.
On the axle of P is pivotted or hinged a frame W, W1, W2, with tooth wheel
gearing D, D1, D2, and pinions P1, P2, P³ The other end of this frame is suspended
and attached to the core C. The upward movement of the core C lifts the whole of
the frames and gear, and first slightly lifts the rack against the inertia of the
movement of the wheels before the train revolves. A further upward movement
brings the rim of the end wheel D² into contact with the adjustable spring K, and
compresses the spring and restrains the rotation of the train of wheels, the rack R
being then lifted, as in the herein before described lamps. The reverse action takes
place upon the core C falling, and the rise and fall of the top carbon is thus
controlled and made gradual instead of being abrupt. The spring K can be
adjusted to stop the rotation of the wheels at any position. We propose to use a
controlling lamp, such as that last described for regulating any desired number of
simple and inexpensive lamps; thus when the frame W is down at its lowest or any
point, it can be made to make contact momentarily and complete the circuit of a
wire connected to electro magnetic coils in any number of lamps, in such a manner
that at the particular moment when an electric current is sent into those coils, it is
made to release all the top carbons, allowing them to drop and feed to the same
extent as they have burnt away. The contact ceasing the carbons are lifted again

page_text: and burn as before. This plan allows the whole of the current to be utilized in
the voltaic ares, except at intervals when a part is shunted off through the coils, as
explained above. Or the circuit may be made to be broken and the electro
magnets to be demagnetized, and thus release the carbons and feed, as before; the
essential features of this controlling system being the use of a good regulator lamp
adapted to give the regulation to any number of other and inexpensive lamps, such
as that shown in Figure 1.
Figures 10 to 17, Sheet 2, of our Drawings show the various improvements we
have made on the incandescent electric light lamps, described in the Specification
to Letters Patent granted to Henry Francis Joel, No. 5157, A.D. 1879; Figure 10
is a sectional view of a lamp somewhat similar to one shown in the said Specifi-
cation. In this lamp there is the addition of an electro magnetic coil S wound
with fine wire, and connected so as to shunt across the burning carbon e. Under
the coil S is an iron flange S¹ to which the rollers R are fixed. The action of this
coil and armature S' is such that should the carbon pencil e fail to make contact
with the top electrode E, the electric current will all pass through the coil S (see
Figure 11), attract the armature S¹, and lift the weight W, and thus take off the
lateral pressure of the jaws J from the pencil electrode e. The pencil electrode
is then subject to the whole of the weight and is pushed forward into contact
again, and the current ceasing to act to the same extent upon the coil S, the
armature S¹ falls, and the weight is again suspended from the tube P and presses
the jaws J upon the pencil electrode e as before. Figures 12 and 13 show a front
and side section of another form of this lamp in which the parts are all reversed, the
weight W is suspended from the rollers R2 and block B, and by means of the
cords W₁ presses the carbon pencil e down, and at the same time by the action of
the flanged tube P pulls the two jaws J together to make good lateral contact upon
the carbon pencil e. The shunt coil S acts in the same manner as in the before
described lamp (Figure 10). The body of this lamp consists of a tube split all the
way down, one half C being fixed to the nipple N and block B at the top, whilst
the other half C¹ is hinged and is in contact with the side arm D supporting the
bottom electrode E. Each half of the tube forms a separate and distinct conductor
for the electric current. The hinged half C¹ is fastened by means of a button and
catch T (see Figure 15) which forms an automatic switch, so that when the tube
is closed the catch T locks it and makes additional contact. Before the tube can
be opened the catch T must be turned and the catch piece brought into contact
with the other part of the circuit C, thus short circuiting the light and lamp. This
enables the lamp to be opened with perfect safety and a new carbon to be placed
in position. There is also an adjustable short circuiting contact at L, which is put
in contact by the shunt S and armature S¹ when excited as before described. Or
it is made to make contact and short circuit the lamp when the carbon is all
consumed by the action of the enlarged socket of the carbon holder and bell crank
lever L, as shown in Figure 13. The connecting wires are brought into this lamp
at A and A', and are clamped by the screws B and B, and thus connected to the
tube C and C. Figure 14 shows another method of applying the shunt coil S.
By this arrangement the coil is placed on the top of the lamp. The action of this
coil is as follows:-When the main circuit is broken, as before described, the
armature S¹ is attracted down, and by means of the stem S² and flange S³ first
binds the cord W₁ in the grooves of the rollers R2, and then slightly presses
down the spring U and so slackens the cord and releases the jaws as before.
Figures 16 and 17 show our method of suspending the lamps. The body of
the lamp is shown in the centre by the tube C, C', and the catch T and globe are
shown at the bottom. The weight or weights G¹ act as a chandelier counterbalance
to the lamp, and the electrical circuit is always kept intact (this being a special
feature in this lamp). The copper cords A, A¹, are connected to the top ceiling
plate, then pass down to the counterweights, and return back over the top pulleys
and round them to the lamp at B, where they are again permanently connected,
the weight or weights G¹ being of course double the weight of the lamp. In

page_text: Figure 17 the globe is taken out by making the holding band H¹ hinged and
fastened by set screws. Figure 10 shows an arrangement of contact jaws in
which the pivotting is avoided and the jaws J are attached to the nipple N by a
buckled spring J' as shown.
Having now described and particularly ascertained the nature of our said
Invention, and the manner in which the same is or may be used or carried into
effect, we would observe in conclusion that what we consider to be novel and
original, and therefore claim as the Invention secured to us by the herein before
in part recited Letters Patent is,-
First. The starting, regulating, and feed movement in an electric light are lamp,
consisting of the combination of the disc D, grip lever L, adjustable screw S, and
solenoid M, substantially as shown and described in reference to Figures 1, 2, and 3
of our Drawings.
Secondly. The modifications of the starting, regulating, and feed movements of
electric light arc lamps, substantially as shown and described in reference to
Figures 4, 5, 6, and 7 of our Drawings.
Thirdly. The application and use to and in the starting, regulating, and feed
movement of electric light are lamps of a train of tooth wheels, substantially as
shown and described with reference to Figures 8 and 9 of our Drawings.
Fourthly. The arrangement and construction of electric light arc lamps,
substantially as shown and described in reference to Figures 1 to 9 of our
Drawings.
Fifthly. The application and use of a standard or controlling regulator arc. lamp
from which any number of other arc lamps are controlled, and the carbons
thereof fed, substantially as described.
Sixthly. The peculiar construction of incandescent electric light lamps,
substantially as described and shown in Figures 10, 12, and 13 of our
Drawings.
Seventhly. The combination with incandescent electric light lamps of a shunt
coil and an armature, arranged and caused to operate substantially as shown and
described in reference to Figures 10, 11, 12, 13, and 14 of our Drawings.
Eighthly. The construction of electric light lamps with a tubular support in
two parts hinged together, each part forming a part of the circuit, substantially as
shown and described in reference to Figures 12, 13, and 15 of our Drawings.
Ninthly. The locking arrangement and automatic switch, substantially as and
for the purpose shown and described in reference to Figures 12 and 15 of our
Drawings.
In witness whereof, I, the said Henry Francis Joel, for myself and on behalf
of the said Andrew Ainslie Common, have hereunto set my hand and seal,
this Ninth day of September, in the year of our Lord One thousand
HENRY FRANCIS JOEL. (L.S.)