Scientific American Supplement, No. 362, December 9, 1882

V >> Various >> Scientific American Supplement, No. 362, December 9, 1882

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[Illustration: FIG. 2--RANQUE'S NEW FORM OF LIGHTER WITH EXTINGUISHER.]

We shall now proceed to the examination of a few practical forms of
electric lighters.

In Fig. 1 will be seen quite a convenient spirit or naphtha lighter,
which has been devised more especially for the use of smokers. By
pushing the lamp toward the wall, the wick is brought into proximity
with the spiral, and the lamp, acting on a button behind it, closes
the current. Pressure on the lamp being removed, the latter moves back
slightly, through the pressure of a small spring which thrusts on the
button. Owing to this latter simple arrangement, the spiral never comes
in contact with the flame, and may thus last for a long time. Mr.
Loiseau, the proprietor of this apparatus, employs a very fine platinum
wire, flattened into the form of a ribbon, and it takes only the current
from a _single element_ to effect the inflammation of the wick. The
system is so arranged that any one can easily replace in a moment the
spiral that has accidentally got out of order; and, in order that this
may be done, the maker has placed the spiral on a small, distinct piece
that he styles the "conflagrator." The latter consists of two small,
thin tubes of brass, held parallel and firmly by means of a brass
cross-piece. A small bit of paper wound round each tube in front of the
cross-brace insures insulation. The outer extremity of the two tubes
supports the platinum spiral, which is fixed to them very simply by the
aid of two small brass needles of conical form, which pinch the wire
in the tube and hold it in place. There is nothing easier to do than
replace the wire. All that is necessary is to remove the two little rods
with a pair of pincers; to make a spiral of suitable length by rolling
the wire round a pin; and to fix it into the tubes, as we have just
explained. With two or three extra "conflagrators" on hand, there need
never any trouble occur.

In Fig. 2 we show a new and simple form of Mr. Ranque's lighter, in
which an electro-magnet concealed in the base brings the spiral and
the wick into juxtaposition. The extinguisher, which is balanced by
a counterpoise, oscillates about a horizontal axis, and its support
carries two small pins, against which act successively two notches in a
piece of oval form, fixed on the side of the movable rods.

In the position shown in the cut, on the first emission of a current the
upper notch acts so as to depress the extinguisher, but the travel of
the rods that carry the spiral is so limited that the latter does not
strike against the extinguisher. On the next emission, the lower notch
acts so as to raise the extinguisher, while the spiral approaches the
wick and lights it. It is well to actuate these extinguishing-lighters,
which may be located at a distance, not by a contact button, but by some
pulling arrangement, which is always much more easy to find in the dark
without much groping about. There might be used for such a purpose the
very motion of the front door, when opened, for lighting the hall; but
that would offer the inconvenience of operating likewise in the daytime,
and of thus needlessly using up the pile and the naphtha. In all these
spirit or naphtha lighters it is important that the spiral _shall not
touch_ the wick, but that it shall be placed a little above and on the
side, in the mixture of air and combustible vapor.

Several apparatus have likewise been devised for lighting gas by
electricity, and a few of these we shall describe.

The simplest form of these is Mr. Barbier's lighter for the use of
smokers, for lighting candles, sealing letters, etc. It consists of a
small gas-burner affixed to a round box, seven to eight centimeters in
diameter, and connected to the gas-pipe by a rubber tube. By maneuvering
the handle, the cock is opened and an electric contact set up of
sufficient duration to raise to a red heat the spiral, and to light the
gas. It is well in this case, for the sake of economizing in wire, to
utilize the lead gas-pipe as a return wire, especially if the pile is
located at some little distance from the lighter. In the arrangement
generally in use the key is provided with a special spring, which tends
to cause it to turn in such a way as to assume a vertical position, and
with a tooth, which, on engaging with a piece moving on a joint, holds
it in a horizontal position as soon as it has been brought thereto. In
order to extinguish the burner, it is only necessary to depress the
lever, and thus allow the key to assume again the vertical position,
that is to say, the position that closes the aperture through which the
gas flows out. In a new arrangement, the notch, spring, and the lever
are done away with, the cock alone taking the two positions open or
closed.

Another very ingenious system is that of Mr. Loiseau, consisting of an
ordinary gas-burner (fish-tail, bat's-wing, etc.), carrying at its side
a "conflagrator," analogous to that of the spirit-lighter (Fig. 1), but
arranged vertically. One of the rods of the "conflagrator" is connected
with the positive of the pile, and the other with the little horizontal
brass rod which is placed at the bottom of the burner. On turning the
cock so as to open it, a small flow of gas occurs opposite the platinum
spiral, while at the same time a rigid projecting piece affixed to the
cock bears against a small, vertical metallic piece, and brings it in
contact with the brass rod. The circuit is thus closed for an instant,
the spiral is raised to a red heat, and lights the gas, and the flame
rises and finally lights the burner. It goes without saying that on
continuing the motion the contact is broken, so as not uselessly to
waste the pile and so as to stop the escape of gas.

For gas furnaces, Mr. Loiseau is constructing a _handle-lighter_ which
is connected with the side of the furnace by flexible cords. The contact
button is on the sleeve itself, and the spiral is protected against
shocks by a metallic covering which is cleft at the extremity and the
points bent over at a right angle. All the lighters here described work
well, and are rendering valuable services. They may be considered as the
natural and indispensable auxiliaries of electric call bells, and their
use has most certainly been rendered practical through the Leclanche
pile.

* * * * *

THEILER'S TELEPHONE RECEIVER.

This telephone receiver differs from its predecessors in dispensing with
an armature, the lateral vibration of the electro-magnet itself being
utilized. In previous systems in which an electro-magnet is used, the
sonorous vibrations are due either to the motion of an iron diaphragm
or armature placed close to the poles of the electro-magnet, or to the
expansion and contraction of the magnet itself. In Theiler's telephone
the electro-magnet may be of the usual U-shape, and may consist either
of soft iron or of hardened steel permanently magnetized, wound with a
suitable number of turns of insulated wire. This electro magnet is fixed
in such a manner that the vibration of either one or of both its limbs
is communicated to a diaphragm or diaphragms The patentees also employ
two or more electro-magnets in the same circuit, and utilize the
vibration of both magnets in the manner described. By attaching a light
disk or disks to the vibrating limbs, the diaphragm may be dispensed
with. Fig. 1 represents one of the telephone receivers provided with two
diaphragms or sounding boards, connected to the two limbs or cores of
the U-shaped electro-magnet by short tongues. These tongues are firmly
inserted in the diaphragms and fixed to the magnet, as shown. The poles
of the electro-magnet are brought very close together by being shaped as
shown, and the middle part of the magnet is firmly screwed to the case
of the instrument. The ends of the helix surrounding the magnet cores
may be attached as usual to two terminals, or soldered to a flexible
conductor communicating with the other parts of the telephone
apparatus. When a vibratory current is sent through the helix of the
electro-magnet, the extremities are rapidly attracted and repelled, and
this vibratory motion of the magnet cores being communicated to the
diaphragms or sounding boards, the latter are set in vibration of
varying amplitude produced by a current of varying strength, as in all
other telephones. Instead of making the electro-magnet of one continuous
piece of iron, as represented in Fig. 1, the patentees find it
more practicable to make it of the form shown in Fig. 2, where the
electro-magnet represented consists of two limbs or cores, a sole piece,
and pole extensions, the whole being screwed together, and practically
constituting one continuous piece of iron carrying the two coils. In
Fig. 2 only one of the limbs or cores of the electro-magnet is attached
to the diaphragm, the other limb being held fixed by a screw. Sometimes
the patentees hinge one of the magnet cores, or both, in the sole piece,
in which case the diaphragms or sounding boards can be made much thicker
than when the cores are rigidly fixed to the sole piece, because
the magnetic attraction of the poles has then only to overcome the
resistance of the diaphragm. Instead of using a diaphragm, they
sometimes fix a stem to one of the cores of the electro-magnet, and
mount thereon a light disk of vulcanite, wood, ivory, gutta-percha, or
any other substance which it is capable of vibrating. When using this
telephone receiver, the disk is pressed to the ear in such a manner
that its surface covers the aperture of the ear. When these telephone
receivers are used on a line of some considerable length, the patentees
prefer to magnetize the electro-magnet by a constant current from
a local battery, and to effect the variation of this constant
magnetization inductively and not directly. The electro-magnet is,
then, not inserted in the line at all, but in the primary circuit of
an induction coil, and connected with a local battery. The line is
connected to the secondry circuit of the induction coil. This device
possesses the advantage that the electro-magnet can be powerfully
magnetized with very little battery power, no matter how long the line
may be, and that steel magnets are entirely dispensed with. It is not
necessary to have a separate battery for this purpose, as the microphone
battery may also be used for the telephone receiver. The shape of the
vibrating electro-magnets is immaterial, as they may be made of a
variety of forms.--_Eng. Mechanic_.

[Illustration: FIG. 1. FIG. 2]

* * * * *

ON AN ELECTRIC POWER HAMMER.

By MARCEL DEPREZ.

[Footnote: _La Lumiere Electrique_.]

In a lecture delivered by me on the 15th of last June in the
amphitheater of the Conservatoire des Arts et Metiers, on the
application of electricity to the production, transmission, and division
of power, I operated for the first time an electric power hammer that I
shall here describe. Its essential part is a sectional solenoid that
I have likewise made an application of in an electric motor which I
presented in July, 1830, to the Societe de Physique. Let us suppose we
superpose, one on the other, a hundred flat bobbins of a centimeter
in thickness in such a way as to form a single solenoid one meter in
height, and that the incoming and outgoing wires of each of them be
connected with the contiguous bobbins exactly in the same way as they
are in the consecutive sections or a dynamo-electric machine ring.
Finally, let us complete the resemblance by causing each junction of the
wire of one of the bobbins with the wire of its neighbor to end in a
metallic plate set into an insulating piece containing as many plates as
there are bobbins, plus one. Over this species of collector, which maybe
rectilinear or wound around a cylinder, let us pass two brushes fixed to
an insulating piece that may be moved by hand. Now, if we place these
two brushes at a distance such that the number of the plates of the
collector included between them be, for example, equal to ten, and we
give them any degree of displacement whatever, after rendering them
interdependent, the current entering through one of these brushes and
making its exit through the other will always traverse 10 bobbins.
Everything will occur, then, as if we caused the ten-bobbin solenoid to
move instead of the brushes. This granted, and the brushes being in any
position whatever, let us send a current into the apparatus, and place
therein a soft iron cylinder. By virtue of a well known law, such
cylinder will remain suspended in the interior of the solenoid, and its
longitudinal center will place itself at so much the greater distance
from that of the solenoid the more the current increases in intensity.
It would even fall entirely if the current had not an intensity above a
minimum value dependent upon many elements concerning which we have not
now to occupy ourselves. We will suppose the current intense enough to
keep the distance of the two centers much below that which would bring
about a fall of the cylinder. When such a condition is fulfilled, it is
found that if we try to remove the iron cylinder from the equilibrium
that it is in, we must apply a pressure that increases with the amount
of separation, just exactly as if it were suspended from a spring. It
results from this fact that if we displace the brushes a distance equal
to the thickness of one plate of the collector, the active solenoid will
undergo the same displacement, and its longitudinal center will move
away from that of the iron cylinder, and that the attraction exerted
upon the latter will increase. It will not be able to assume its first
value, and equilibrium cannot be re-established unless the cylinder
undergoes a displacement identical with that of the solenoid. Now,
as this latter depends upon the motion communicated to the system
of brushes, we see that, definitively, the cylinder will faithfully
reproduce the motion communicated to the brushes by the hand of
the operator. This apparatus, then, constitutes a genuine electric
servo-motor in which the current is never interrupted nor modified in
quantity or direction, no more indeed than the magnetization developed
in the soft iron cylinder. Everything takes place as if the iron
cylinder were suspended in a solenoid ten centimeters in length that
was caused to rise and fall; with the difference that the weight of the
cylinder exerts no action on the hand of the operator.

[Illustration: ELECTRIC POWER HAMMER.]

These explanations being understood, there remain but few things to be
said to cause the operation of the hammer to be thoroughly comprehended.
The elementary sections constituting the electric cylinder, A B, of the
hammer are 80 in number, and form a total length of one meter. Their
ingoing and outcoming wires end in a collector of circular form shown at
F G. The brushes are replaced by two strips, C E and C D, fixed to the
double winch, H C I, which is movable around the fixed center, C. They
can make any angle whatever with each other, so that by trial there
maybe given the active solenoid the most suitable length. When such
angle has been determined, the angle, E C D, is rendered invariable by
means of a set screw, and the apparatus is maneuvered by imparting to
the double winch, H C I, an alternating circular motion.

The iron cylinder weighs 23 kilogrammes; but, when the current has an
intensity of 43 amperes and traverses 15 sections, the stress developed
may reach 70 kilogrammes; that is to say, three times the weight of the
hammer. So this latter obeys with absolute docility the motions of the
operator's hands, as those who were present at the lecture were enabled
to see.

I will incidentally add that this power hammer was placed on a circuit
derived from one that served likewise to supply three Hefner-Alteneck
machines (Siemens D{5} model) and a Gramme machine (Breguet model P.L.).
Each of these machines was making 1,500 revolutions per minute and
developing 25 kilogrammeters per second, measured by means of a
Carpentier brake. All these apparatus were operating with absolute
independence, and had for generator the double excitation machine that
figured at the Exhibition of Electricity.

In an experiment made since then, I have succeeded in developing in each
of these four machines 50 kilogrammeters per second, whatever was the
number of those that were running; and I found it possible to add the
hammer on a derived circuit without notably affecting the operation of
the receivers.

It results from this that with my system of double excitation machine I
have been enabled to easily run with absolute independence six machines,
each giving a two-third horse-power. The economic performance, e/E,
moreover, slightly exceeded 0.50.

* * * * *

SOLIGNAC'S NEW ELECTRIC LAMP.

When it becomes a question of practical lighting, it is very certain
that the best electric lamp will be the one that is most simple and
requires the fewest mechanical parts. It is to such simplicity that is
due all the success of the Jablochkoff candle and the Reynier-Werdermann
lamp. Yet, in the former of these lamps, it is to be regretted that the
somewhat great and variable resistance opposed to the current in its
passage through two carbons that keep diminishing in length, in measure
as they burn, proves a cause of loss of light and of variation in it.
And it is also to be regretted that the duration of combustion of the
carbons is not longer; and, finally, it is allowable to believe that the
power employed in volatilizing the insulator placed between the carbons
is prejudicial to the economical use of this system. In order to obviate
this latter inconvenience, an endeavor has been made in the Wilde candle
to do away with the insulator, but the results obtained have scarcely
been encouraging. An endeavor has also been made to render the duration
of the carbons greater by employing quite long ones, and causing these
to move forward successively through the intermedium of a species
of rollers, or of counterpoises, as in the lamps of Mersanne and
Werdermann; but then the system becomes more complicated. Finally, in
order to keep the resistance of the carbons at a minimum and constant,
their contact with the rheophores of the circuit has been established
at a short distance from the arc, and this is one of the principal
advantages possessed by the Reynier-Werdermann system. At a certain
epoch it was thought that the problem might be simply solved by
arranging in front of each other two carbons actuated by a spiral
spring, as in car lamps, and kept at a proper distance apart for forming
the electric arc by two funnel-shaped pieces of calcined magnesia, into
which they entered like a wedge in measure as their conical point were
away through combustion. This was the system of Mr. De Baillehache,
and the trials that were made therewith were very satisfactory. But,
unfortunately, the magnesia was not able to resist very long the
temperature to which it was submitted. The problem found a better
solution in the sun-lamp but has been solved in another manner, and just
as simply, by Mr. Solignac, and the results obtained by him have been
very satisfactory as regarded from the standpoint of steadiness of the
luminous point.

In this system, a general view of which is given in Fig. 1, and the
arrangement in Figs. 2 and 3, the carbons, F F, which are horizontal and
about fifty centimeters in length, are thrust toward each other by
two barrels, K, K, which wind up two chains, E, E, passing around the
pulleys, D, D, fitted to the extremities of the carbons. These latter
are provided beneath with small glass rods, G, G, whose extremities
toward the arc abut at a short distance from the latter against a nickel
stop, L (Fig. 3), which supports them, moreover, at M, by means of
a tappet whose position is regulated by a screw. The current is
transmitted to the carbons by two friction rollers, I, I, which serve at
the same time as a guide for them, and which give the electric flux a
passage of only one or two centimeters over the front of the carbon
to form the arc. Finally, the whole is held by a support, A, and two
pieces, CB, CB, which at the same time lead the current to the friction
rollers through projections, J. The two systems are made to approach
or recede from each other, in order to form the arc, by means of a
regulating screw, H.

At present, the lighting of these lamps is effected by means of this
screw, H, but Mr. Solignac is now constructing a model in which the
lighting will be performed automatically by means of a solenoid that
will react upon a carbon lighter, as in several already well known
systems.

[Illustration: Fig. 1]

If the preceding description has been well-understood, it will be seen
that the carbons are arrested in their movement toward each other only
by the glass rods, G, abutting against L; but, as the stops, L, are not
far from the arc, and as the heat to which they are exposed is so much
the greater in proportion as the incandescent part of the carbons is
nearer them, it results that for a certain elongation of the arc the
temperature becomes sufficient to soften the glass of the rods, G, G,
so that they bend as shown at O (Fig. 3), and allow the carbons to move
onward until the heat has sufficiently diminished to prevent any further
softening of the glass. In measure as the wearing away progresses, the
preceding effects are reproduced; and, as these are produced in an
imperceptible and continuous manner, there is perceived no jumping nor
inconstancy in the light of the arc. Under such conditions, then, the
regulation of the arc is effected under the very influence of the
effect produced; and not under that of an action of a different nature
(electro-magnetism), as happens in other regulators. It is certain that
this idea is new and original, and the results that we have witnessed
from it have been very satisfactory. There is but one regulation to
perform, and that at the beginning, but this once done the apparatus
operates with certainty, and for a long time. With a Meritens machine of
the first model it has been found possible to light five lamps of this
kind placed in the same circuit.

[Illustration: Fig. 2]

According to the inventor, this lamp will give a light of 100 carcels
per one horse-power, and with a three horse-power six lamps may be
lighted; but we have made no experiments to ascertain the correctness of
these figures.

As for the cost of the glass rods, that amounts to one franc per
two hundred meters length. They can, then, be considered only as an
insignificant expense in the cost of the carbons. We consequently
believe that it will be possible to employ this system advantageously in
practice.--_Th. du Moncel_.

[Illustration: Fig. 3]

* * * * *

MONDOS'S ELECTRIC LAMP.

Since the month of May last, the concert at the Champs Elysees has been
lighted by sixteen voltaic arc lamps on a new and very simple system,
which gives excellent results in the installation under consideration.
The sixteen lamps are on the divisible system, and their regulation is
based upon the principle of derivation. They are supplied by a Siemens
alternating current machine and arranged in four circuits, on each of
which are mounted four lamps in series. The accompanying figures will
allow the reader to readily understand the system, which is as simple
as it is ingenious, and which has been combined by Mr. Mondos so as to
obtain a continuous and independent regulation of each lamp.

In this system the lower carbon is stationary, the luminous point
descending in measure as the carbons wear away through combustion. The
upper carbon descends by its own weight, and imperceptibly, so as to
keep the arc at its normal length.

The mechanism that controls the motions of the upper rod that supports
the carbon-holder consists of two bobbins of fine wire, E (Fig. 2),
mounted on a derived circuit on the terminals of the lamp; of a lever,
L, articulated at O, and supporting a tube, TT', and the whole movable
part balanced by a counterpoise, P. This lever, P, carries two soft iron
cores, F, which enter the bobbins, E, and become magnetized under the
influence of the current that passes through them. The upper part of
the tube, T, carries a square upon which is articulated at O' a second
lever, L', balanced by a second counterpoise, P', and carrying a flat
armature, _p_, opposite the cores, F', that are fixed to the first
horizontal lever, L. The carbon-holder rod, CC', slides freely in the
tube, TT', and is wedged therein by a small piece, _a m l_, fixed to
the lever, L'. For this reason the tube, TT', is provided with a notch
opposite the piece _a m l_, and the two arms, _a_ and _m_, of the latter
are shaped like a V, as may be seen in part in the plan in Fig. 2. It is
now easy to understand how the system operates; when the current is not
traversing the circuit, the carbons are separated; but, at the moment
the circuit is closed for lighting a series of lamps, it traverses the
electro-magnet, which then becomes very powerful, and draws down the
cores, F, along with the lever, L, the tube, TT', and the carbon-holder,
CC', and brings the carbons in contact. The arc then forms, and the
current divides between the arc and the bobbins, E. Its action upon the
cores, F, becomes weak, and it can no longer balance the counterpoise,
P, which falls back, and raises the system again. The arc thus
becomes _primed_. The cores, F, however, preserve a certain amount of
magnetization; the armature, _p_, is attracted, and the lever, L',
assumes a position of equilibrium such that the piece, _a m l_, wedges
the rod, CC', in the tube, TT', and holds it suspended. When, through
wear of the carbons, the arc elongates, a greater portion of the current
passes into the bobbins, E, the armature, _p_, is attracted with more
force, and the lever, L', swings around the point, O'. The rotation of
L' separates the piece, _a m l_, from the rod, CC', which, being thus
set free, slides by its own weight and shortens the arc. The current
then becomes weak in E, the armature, _p_, is not so strongly attracted,
the lever, L', pivots slightly around O' under the action of the weight,
P', and the brake or wedge enters the notch anew, and stops the descent
of the carbon. In practice, the motions that we have just described are
exceedingly slight; the carbon moves imperceptibly, and the length of
the arc remains invariable.

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