IMPROVEMENTS IN ELECTRIC LIGHTING APPARATUS, WHICH INVENTION COMPRISES MECHANISM APPLICABLE FOR OTHER PURPOSES
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the Office of
the Commissioners of Patents on the 8th July 1881. A communication from
abroad by John James Conrad Wilhelm Greb, of Frankfort on the Main, in
the Empire of Germany.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent
Agents, Southampton Buildings, London. "IMPROVEMENTS IN ELECTRIC LIGHTING
APPARATUS, WHICH INVENTION COMPRISES MECHANISM APPLICABLE FOR OTHER
PURPOSES." [A communication from abroad by John James Conrad Wilhelm Greb,
of Frankfort on the Main, in the Empire of Germany.]
This Invention relates to improvements in electric lamps or lighting apparatus,
the mechanism of which provides for a very sensitive and exact regulation, so that
a number or series of the said lamps may be included in the circuit of a continuous,
weak, or intermittent current in such a manner that oue lamp will not disturb or
interfere with the action of another, and, notwithstanding the most sensitive
regulation, the luminous point always remains the same as both carbons approach
each other. Part of the mechanism is applicable for other purposes.
A lamp or lighting apparatus constructed according to this Invention comprises
three essential parts, consisting of (1) a train of toothed gearing or clockwork for
transmitting and multiplying the motion of the carbons, this mechanism being
operated or set in motion by the weight of the upper carbon; (2), repelling mechanism
for causing the carbons to recede from each other, so that the light may be
developed; and (3), mechanism for causing the carbons to approach nearer to each
other as they are consumed; and these three parts of the apparatus are controlled
by a locking or holding device which connects the gearing or clock work with the
repelling mechanism and with the approaching mechanism, or disconnects it there-
from as required in the manner hereinafter described.
The clock-work or gearing consists of the following parts, that is to say:-
:-There
is an axle or shaft carrying two cord-pulleys, around or over which pass cords
connected with the carbon-holders, and on the same shaft there is a toothed wheel,

page_text: which gears with a pinion on an arbor or spindle, upon which there is a ratchet-
wheel provided with two pawls. On the same spindle there are two toothed
wheels, one on each side of the ratchet-wheel, and below these wheels there is a
spindle carrying at one end a star-wheel, and at the other end a pinion, which is in
gear with one of the toothed wheels above mentioned.
The star wheel, in addition to the conical teeth which impart to it the star-shape,
is provided with pins or studs on one face. The pins or studs may however be
replaced by small steel plates connected with the pointed conical teeth. An
escapement-lever fits this wheel, and is pivotted to a part of the frame-work of the
lamp. Instead of the pins or steel plates I may employ a second escapement-wheel
made with as many teeth as there would be pins. Over the point of rotation there
is a small cross piece which forms an inclined plane. This star-wheel arrangement
or escapement may, with or without modifications, be used advantageously in
clock work not in connection with electric lighting apparatus. For repelling the
carbons from each other I provide an electro-magnet having a pivotted armature
above the same, and in connection with this armature there is a rod or bar, one end
of which takes into the teeth of one of the aforesaid toothed wheels, which it causes
to rotate, and thus to operate the toothed wheel on the first named shaft. I also
provide a branch-current electro-magnet, the armature of which is an extension
from the rear end of the first named armature, and there is a circuit-breaking or
current-interrupting device connected with the armature arm or lever by means of
a chain. There is also a releasing armature for operating the locking or holding
device as required.
For causing the carbons to approach each other as they burn away I provide a
second branch-current magnet, also an armature having in connection therewith a
counterweight, a releasing roller for operating the locking or holding device, a pawl
or projection for engaging with the star-wheel, and a lever or piece communicating
with a vessel containing mercury to break the circuit or interrupt the current.
When the lamp or apparatus is not in operation the points of the carbons rest in
contact with each other, and the parts of the mechanism are all in such relative
positions that they are ready to operate automatically immediately the current
enters the apparatus. When the electric current enters it flows through the
electro-magnet first herein mentioned, whereupon that end of the pivotted armature
which is immediately above this magnet is attracted to the same, and as the other
end consequently rises the rod or bar in connection therewith pushes the toothed
wheel with which it engages, so that the ratchet-wheel on the same shaft is also
rotated to the extent of one or two teeth, and thus the carbons are caused to
separate slightly. The said armature would remain attracted to the electro-magnet,
and the rod or bar would also remain in connection with the toothed wheel were
there not some provision for interrupting the current. I therefore provide means
whereby this current is interrupted immediately the operation of separating the
carbons has taken place, but the circuit is made again immediately, and the arma-
ture is attracted again if the carbons have not been separated to a sufficient extent,
and this making and breaking goes on automatically until the proper distance is
attained for causing the light to be developed between the carbon points. This
operation is effected by means of the device above mentioned as being connected
to the armature by a chain.
This chain is secured at its other end to a pivotted lever, one end of which dips
into mercury contained in a vessel. Whilst the armature is at rest the lever is in
contact with the mercury, and the circuit through the magnet is complete, but
when the armature is attracted by this magnet the chain lifts the lever, and the
current cannot pass through the said magnet. The interruption sparks are very
small as the current continues to flow, but it then passes through the magnet of a
resistance apparatus, so that properly speaking the branch current only is
interrupted.
At the moment at which the carbons become sufficiently separated the electro-
motive force becomes stronger in the branch-current electro-magnet which is in

page_text: connection with the other end of the armature than in the first named magnet,
therefore this branch current magnet keeps the arinature attracted thereto in its
position of rest. In this condition of the mechanism the carbon points would come
together again, were it not for the devices which I will now proceed to describe.
A releasing armature is at one end in connection with the first named electro-
magnet, and at the other end with a lever for operating the locking or holding
device. When the current passes through this magnet it attracts this armature
and allows the locking device to fall into the star-wheel, and thus the clockwork
or gearing is held or locked, and consequently the carbons cannot move until it
becomes necessary for them to approach each other by reason of the combustion of
the same.
To effect this the second branch magnet and mechanism connected
therewith are provided, and the current through this magnet does not cross or pass
over the voltaic arc; the resistance of the latter determines the power of the said
magnet. When the latter has reached its maximum power the armature in
connection with this magnet is attracted thereto, and the releasing roller in
connection with this armature presses upon the holding or locking device and thus
lifts the same out of the star-wheel, and at the same time the escapement pin or
projection falls in on the other side, so that at each operation of the magnet the
carbons can approach each other only to a very slight extent. If the movement is not
sufficient to allow the counterweight in connection with the armature to overcome
the attractive force of the magnet, the operation will be repeated until equilibrium
is re-established. Each time that the attraction takes place the branch current is
interrupted by a lever or piece, hereinbefore mentioned, which is connected with
the armature by a chain, and which dips into a second mercury vessel. When the
attraction occurs, the lever is lifted out of contact with the mercury, whereby the
circuit is broken and the attraction ceases. This armature has upon it a pawl or
projecting piece, also a vertical extension which carries the releasing roller herein-
before mentioned; this roller works upon an inclined plane hereinbefore mentioned.
The pawl or projecting piece, when the armature is at rest, is outside the star-
wheel, and the roller does not press upon the inclined plane; therefore the locking or
holding device is allowed to fall by the action of a weight upon the same between
the pins upon the star-wheel, so that the clockwork is held or locked until the
armature is attracted by the magnet, whereupon the roller is caused to bear upon
the inclined plane and so removes the locking or holding device from the star-
wheel, and at the same time the pawl or projecting piece takes into the said wheel.
When the armature again recedes, the locking device again drops into the wheel
and liberates the pawl. To prevent the armature from falling back too far, I provide
a stop. The movement which the clock work is to have at each release thereof
depends upon the distance of the pawls from the conical shaped teeth of the star-
wheel; the distance may be varied to suit various circumstances.
The mercury-vessel for interrupting the main current may consist of several
small vessels separated and insulated from one another, so that the inflowing current
can be conducted to the first named electro-magnet in several branch-currents,
whereby smaller interruption-sparks will be produced than otherwise; or the vessel
may contain a float of platinum or copper placed in the mercury.
To ensure the proper working of the lamps a resistance-apparatus is provided,
and if by reason of accident the light in a lamp should be extinguished the circuit
will be closed, and when the carbons come into contact again the light will be
again developed automatically, as a lamp may be cut out or inserted without
causing any inconvenience to the others of the series. The power for operating
this resistance-apparatus is supplied by a branch current from the one which passes
through the voltaic arc, and the material for producing the resistance is carbon and
not wire as usual. I provide rods of carbon, which have the tendency to replace
the resistance offered by one apparatus, and this is rendered possible by placing
several rods side by side, which being connected in suitable length and number
allow the degree of resistance to be ascertained to the smallest fraction. To this
end a rod of carbon, upon which is placed a metal slide supplying the current, is

page_text: used for ascertaining the fractions; the other carbon-rods through which the
current passes indicate units of a certain power of resistance. The slide may be
moved either by a screw, or if the apparatus is used for work remaining constantly
the same, it may be set to the proper degree by hand.
This apparatus is used not only for cutting a lamp out of the circuit, but it may
also be used, when inserted in the circuit of the current flowing through a lamp,
to diminish or altogether to extinguish the light of such lamp as required.
The parts of this apparatus are as follows:-An electro magnet, an armature,
two contact-plates, a mercury vessel, an armature rod, carbon-rods, a copper-rail,
and a setting slide. When the current enters the lamp the armature is attracted,
and that current which flows through the contact-plates is interrupted, so that the
whole power of the current must take its way through the lamp. The apparatus
remains in this condition till the light is extinguished, at which moment the
armature falls away from the electro-magnet by its own weight, and the current
flows through the contact-plates into the carbon-rods of another lamp; in the same
manner as a resistance apparatus may be connected with the contact apparatus
another lamp may be connected therewith.
The following modifications may be made in my electric lighting apparatus or
lamp, that is to say, in the mechanism for causing the carbons to approach each
other, an electro-magnet excited by a branch current passing through the voltaic
arc may replace the counter-weight.
The releasing armature for the locking device, which is operated by the main
electro-magnet, may be replaced by a branch current magnet, also excited by a
current passing through a voltaic arc, and causing, independently of the first-
named electro-magnet, by a separate transmitting armature, the operation of the
said device.
The interrupting devices for the first electro-magnet may be dispensed with, and
the repelling of the carbons effected by a pallet or a small toothed wheel. Such
pallet or toothed wheel must, after completion of the stroke (that is to say, after
repelling the carbons) be released automatically, after which the first named
armature lever remains continually attracted by the first electro magnet whilst the
lamp is burning. The releasing armature is in that case also omitted, and it is the
said armature lever alone which, in connection with an inclined plane, causes the
locking device to drop into the star-wheel, or raises the same out of the latter,
thereby releasing it. The locking device drops into the said wheel when the
armature-lever is attracted, and the locking device is released as soon as the
armature-lever returns to its position of rest.
The lower or negative carbon may be so arranged as to have only so much
motion as is requisite for repelling the carbons from each other. This repulsion
for the development of the light may be effected either by a solenoid or by an
electro-magnet, the mechanism for drawing the carbons nearer remaining the same;
in this case, therefore, the repelling mechanism is altogether omitted, and a branch
current is used for operating the locking device. The repelling magnet acts directly
upon the negative tube or holder.
Instead of iron armatures permanent magnets may be used, and instead of the
current-interrupting-device, whereby the armatures fall, or vice versa, for producing
contact and for attracting the armatures, change in the current will act upon the
permanently magnetic armatures by change of the polarity of the electro-magnet,
which is produced as follows, and causes repulsion or attraction. In the repelling
mechanism I provide instead of the interrupting mercury vessel two vessels at each
side of the point of rotation of the armature lever, the current thus passing into
the electro-magnet, and polarity contrary to that of the permanently magnetic
armature lever being produced in the former, a tendency to attract is caused; as
soon as the armature is attracted the current is closed by the other two contacts,
and, passing through the electro-magnet, the like polarity as that of the
permanently magnetic armature is produced in the electro-magnet, and instead of
being attracted the armature is repelled, which is repeated till the correct distance

page_text: between the carbons is attained and the power of the branch magnet brings the
armature-lever to rest.
This principle of changing the current may also be used for the mechanism
for causing the carbons to approach each other instead of the principle of
interruption, provided that permanent magnets are used instead of the iron
armatures.