IMPROVEMENTS IN THE PRODUCTION OF ELECTRIC LIGHT FOR SIGNALLING AND OTHER PURPOSES, AND IN APPARATUS OR MEANS EMPLOYED THEREFOR AND IN CONNECTION THERE- WITH."
Year: 1876

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
THE PRODUCTION OF ELECTRIC LIGHT FOR SIGNALLING AND OTHER PURPOSES,
AND IN APPARATUS OR MEANS EMPLOYED THEREFOR AND IN CONNECTION THERE-
WITH." A communication from abroad by François Ernest de Mersanne, of
Paris, in the Republic of France,
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 23rd August 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN THE PRODUCTION OF ELECTRIC LIGHT FOR SIGNAL-
LING AND OTHER PURPOSES, AND IN APPARATUS OR MEANS EMPLOYED THEREFOR AND
IN CONNECTION THEREWITH A communication from abroad by François Einest
de Mersanne, of Paris, in the Republic of France.
"
23
This Invention relates to a new description of electric lamp (more especially
applicable to the production of signals arranged in such a manner as to effect from
a distance the instantaneous kindling or extinguishing of a light or of a signal as
well as all possible movements of the carbon points. For example, by means of this
Invention the following motions of the carbon points may be produced as desired,
viz.One carbon alone may be caused to.. move upwards or downwards.
The
two carbons together may be caused to move up or down without being extinguished.
The two carbons may be caused to move towards or away from each other simul
taneously. Whence it results that the proper distance between the carbons may
always be maintained during the continuance of a signal, and the focus of light be
kept exactly in the optical focus of the lamp, and that even if a carbon should
happen to break it will be simply necessary to bring them nearer together until
they light again, and raise or lower them until the light has returned to the optical
centre.
All these movements may be produced by hand at a distance, but in this way
also the lighting and extinguishing and focussing only can be effected, the function
of automatically regulating the light during the signal being perforined by a special
applianco annexed.to the manipulator, and which can be arranged in such a manner
A

page_text: that this action is produced without the illuminating current intervening in this
manipulator.
The lamp is based upon the following principle, viz-An auxiliary current is
taken from any source, or even from the machine serving for the production of the
light In the circuit of this current there are provided certain appliances contained
in the base or foot of the lamp and a manipulator which produces the signals. In
closing this auxiliary current by suitable contact makers upon the manipulator all
the functions above indicated are performed instantaneously. Two or more auxiliary
currents may be employed if required.
In carrying out this Invention the mechanism of the lamp is composed of the
following parts, viz. :-Two screws enclosed in the hollow columns for causing two
nuts which serve as carbon holders to ascend or descend. These screws pass through
the base or stand of the apparatus, and are each provided at that part with two
ratchet wheels, the teeth of which are inclined in opposite directions, and with
which engages a pawl situate between the two wheels. This pawl oscillates
between two bobbins which attract it in one direction or the other. It is jointed
to a support arranged in such a manner as to allow it to move vertically, whilst the
support itself turns upon two pivots which admit of its moving horizontally so as
to yield to the attraction of one or the other of two electro-magnets firmly secured
to a fixed bracket in which the support oscillates. Under these conditions if the
person making the signals touches the proper contact maker the pawl will engage
with a tooth of the upper wheel for example, in consequence of the attraction of the
corresponding bobbin, then by touching another contact maker the corresponding
electro-magnet will effect a lateral motion which will draw the wheel with it and
cause the screw to rotate in this movement, the nut and carbon holder will be
elevated for example to a height previously calculated. The reverse motion may
be imparted to the same screw, that is to say, it may be caused to 10tate in the
opposite direction and cause the nut to descond by producing the two corresponding
contacts in the manipulator. In a similar manner the two corresponding motions
are imparted to the other screw. For example, assume two bobbins and two
electro-magnets (arranged in the manner before inentioned), herein-after designated
bobbins, and electro-magnets Nos. 1 and 2; let a branch current derived from the
source of the light be taken and conducted by means of a suitable wire, one end of
which is to be united with the two bobbins, let the other end of the wire on the
bobbin be placed in connection with electro-magnet No. 1, and with a binding sciew
or contact point; then take the other end of the wire of the electro-magnet No. 1
and place it in connection with another binding screw or contact point, proceed in
like manner with the bobbin No. 2 and electro-maguet No. 2, and place the
extremities of the wires in connection with two other binding screws or contact
points. Let it be assumed that the bobbin No 1 and the electro-magnet No. 1
correspond with the ratchet wheel which causes the nut to ascend, and that tho
bobbin No. 2 and the electro-magnet No. 2 correspond with the wheel which causes
the nut to descend. Then, if the other extremity of the branch wire constituting a
contact maker be placed in communication with the binding screw or contact point
first mentioned, only the current will pass through the bobbin No. 1 aloue, and the
pawl will engage with the wheel for effecting the ascensional motion. Then if the
contact maker be placed in contact with the binding sciew or contact point secondly
mentioned without leaving the former, the current will continue to pass through
the bobbin No. 1 only, as the branch current derived by the electro-magnet is under
conditions which are too unfavourable to allow it to take effect. But the pawl will
still remain engaged with the wheel, and at the moment when the contact with the
binding screw first mentioned is broken so as to pass over to the binding screw
secondly mentioned, the current will be compelled to pass through at the same time
both the bobbin and the electro-magnet. They will, therefore, both work together,
the screw will revolve and the nut will be elevated to a certain height. It is thus
evident that in order to raise the nut it suffices to cause the contact maker to pass
over the two contact points, care being taken that the contact commences on the

page_text: first alone, it being in the next place common to both, and terminating on the
second alone. In order to cause the nut to descend it is simply necessary to
operate in a similar manner with the two other contact points in the reverse
direction.
The two corresponding movements of the other screw will be obtained in like
manner, the same derived or branch current may be utilized by closing the circuit
on the four other binding screws or contact points of an apparatus resembling that
herein-before described.
The manipulator consists of two insulating handles, each corresponding with one
of the two screws of the lamp, which handles are secured to an insulating plate. One
of the handles carries two sets of springs insulated from one another. Upon the
insulating plate there are provided four contact points which are in communication
with the binding screws before mentioned. By the side of each of these contact
points there is a contact maker, and these contact makers are placed in such a
manner that the springs of the handle place them in communication two by two.
Two of the contact makers which communicate with two alternate contact points
come into communication with one contact plate. In like manner the two other
alternate contact points are placed in communication with another contact plate,
the two plates being arranged in such a manner that by passing a metallic brush
over them in the required direction the necessary conditions will be fulfilled.
A similar arrangement is employed for the other handle which is destined to act
upon the second screw of the lamp.
In order to produce the light the following effects are obtained by the operation
of the apparatus herein-before described.
1st. The carbons are placed in contact by bringing one of them near to the
other. At the moment when they come into contact notice is given of the same
either by a indicating needle or by a platinum wire which becomes heated to
redness.
2ndly. As soon as this indication is given, the carbons are drawn a short distance
apart by a single contact.
3rdly. The lighting bobbin is next worked, which bobbin being fixed to the
lower carbon causes a sufficient vibration to produce the contact, and immediately
after the separation the instantaneous lighting takes place.
These precautions are not necessary except for the first lighting, for the successive
operations of lighting the carbons will be already separated, it is simply necessary to
work the lighting bobbin
This lighting bobbin consists simply of a bobbin secured firmly to the lower
carbon holder, it acts under the influence of the same auxiliary current as serves
for the other movements. When it commences to move, its vibrations are com-
municated to the lower carbon, and if this latter should happen to be situate near the
upper carbon a contact ensues followed by the recoil necessary to the instantaneous
formation of the arc, and the illumination is produced.
The lamp is completely enveloped in a case provided at its contral portion with
an optical arrangement, at the centre of which the light of the lamp should flash,
The mechanism of the electro-magnets,- levers, ratchet wheels, pawls, and other
necessary working parts are likewise enclosed in a case which entirely protects
them from all external shocks
The carbons may be brought together automatically, so as to maintain them at
the required distance notwithstanding the constant wear to which they are subjected,
by the employment of an apparatus composed of a clockwork motion, the speed of
which may be readily adjusted by means of a key or of a button, and which serves
to inaintain in uniform motion a metallic brush or rubber performing the functions
of the frictional contact maker of the branch wire herein-before referred to. In this
case the contact points are disposed upon a vertical board fitted to the fixed table
which is placed under the hand of the operator; they are, moreover, arranged
around the centre of rotation of the clockwork motion in such a manner that the

page_text: contact making brush passes over them continually in the order required for causing
the carbons to approach one another constantly in proportion as they become worn.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the
22nd February 1877.
"
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman "IMPROVEMENTS IN THE PRODUCTION OF ELECTRIC LIGHT FOR SIGNAL-
LING AND OTHER PURPOSES, AND IN APPARATUS OR MEANS EMPLOYED THEREFOR AND
IN CONNECTION THEREWITH." A communication from abroad by François Ernest
de Mersanne, of Paris, in the Republic of France.
The said Invention relates to a new description of electric lamp (more especially
applicable to the production of signals) arranged in such a manner as to effect from
a distance the instantaneous kindling or extinguishing of a signal or other light, as
well as all possible movements of the carbon points or electrodes
For example, by
means of this Invention the following motion of the carbon points may be produced
as desired, videlicit:-One carbon alone may be caused to move upwards or down-
waids The two carbons together may be caused to move up or down without
being extinguished. The two carbons may be caused to move towards or away
from each other simultaneously. It results from the foregoing that the proper
distance between the carbons may always be maintained during the continuance of
a signal, and the focus of light be kept exactly in the optical focus of the lamp, and
that even if a carbon should happen to break it will be simply necessary to bring
them nearer together until they are relighted, and raise or lower them until the
light has returned to the optical centre.
The whole of these movements may be produced by hand at a distance, but in
this way the lighting, extinguishing, and focussing only can be effected, the function
of automatically regulating the light during the signal being performed by a special
appliance annexed to the manipulator, and which can be arranged in such a manner
that this action is produced without the illuminating current intervening in this
manipulator.
•
The lamp is based upon the following principle, videlicit:-An auxiliary current
is taken from any suitable source, even from the machine serving for the production
of the light In the circuit of this current there are provided certain appliances
contained in the base or foot of the lamp, and a manipulator which produces the
signals. In closing the circuit of this auxiliary current by suitable contact makers
upon the manipulator, all the functions above indicated are instantaneously performed.
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same, and for that purpose shall refer
to the several Figures on the annexed Sheet of Drawings, the same letters of
reference indicating corresponding parts in all the Figures
Figure 1 of the accompanying Drawings is a sectional elevation of a lamp con-
structed according to this Invention; and Figure 2 is an external elevation of
the same.
Figures 3, 4, 5, 6, and 7 illustrate details of the mechanisin for adjusting the
carbon points and effecting the lighting; and Figures 8, 9, and 10 represent the
manipulators
Inside the lamp (Figures 1 and 2) there are provided two screws D, D¹, enclosed
in two hollow columns 1, 2, for causing two nuts E, E¹, respectively, which serve as
carbon holders to ascend or descend; these screws pass through the base or stand 3
of the apparatus, and are each provided at that part with two ratchet wheels, one
pair of which only are shown in the Drawing maiked F, G, Figures 1 and 3, having
their teeth inclined in opposite directions, with which engages a pawl C situate

page_text: between the two wheels. This pawl oscillates between two bobbins A, B, which
attract it in one direction or the other, it'is jointed at 4 to a support 5 arranged in
such a manner as to allow it to move vertically, whilst the support itself is capable
of turning upon two pivots 6, 6, in a fixed frame 7, which admit of its moving holi-
zontally so as to yield to the attraction of one or the other of two electro-magnets
A¹, B¹ firmly secured to the fixed frame 7 in which the support 5 oscillates. Under
these conditions if the attendant making the signals touches the proper contact
maker the pawl C will engage with a tooth of the upper wheel F, for example, in
consequence of the attraction of the corresponding bobbin, then by touching another
contact maker the.corresponding electro-magnet will effect a lateral motion which
will draw the wheel with it and cause the screw to rotate; in this movement the
nut and carbon holder E will be elevated, for example, to a height previously
calculated. The reverse motion may be imparted to the same screw, that is to say,
it may be caused to rotate in the opposite direction, and cause the nut to descend
by producing the two corresponding contacts in the manipulator. In a similar
manner the two corresponding motions are imparted to the screw D¹.
Refering to Figure 5, let S be the source of light, and let for example branch
currents be taken and conducted by means of wires, the extremities of which are to
be united with two bobbins A, B, respectively. Let the other end of the wire on
the bobbin A be placed in connection with an electro-magnet A¹ and with a binding
screw or contact point a, and the other end of the wire of the electro-magnet A' be
placed in connection with another binding screw or contact point b proceed in like
inanner with the bobbin B and electro magnet B¹, and the two binding screws or
contact points c, d Let it be assumed that the bobbin A and the electro-magnet A¹
correspond with the ratchet wheel which causes the nut to ascend, and that the
bobbin B and the electro-magnet B¹ correspond with the wheel which causes the
saine nut to descend. Let M be the other extremity of the branch wire; then if M
be placed in communication with the binding screw or contact point a only the
current will pass through the bobbin A only, and the pawl will engage with the
wheel for effecting the ascending motion; then if M be placed in contact. with b
without leaving a the current will continue to pass through the bobbin A only, as
the branch current derived by the electro-magnet is under conditions which are too
unfavourable to allow it to tako effect; But the pawl will still remain engaged with
the wheel F, and at the moment when the contact with a is broken so as to pass
over to b the current will be compelled to pass at the same time through both
the bobbin and the electro-magnet; they will therefore both work together, the
screw D, Figure 3, will revolve, and the nut E will be elevated to a certain height.
It is thus evident that in order to raise the nut E it is simply necessary to cause
the contact maker M to pass over the two contact points a, b, in the direction of
the arrow, care being taken that the contact commences on a alone, that it is in the
next place common to both a and b, and that it terminates on b alone. In order
to cause the nut to descend it is simply necessary to operate in a similar manner
with the two contact points c, d, in the direction of the arrow.
The two corresponding movements of the other screw D¹ will be obtained in like
manner, the same branch or derived current may be utilized by closing the circuit
on 4, other binding screws or contact points of an apparatus resembling that herein-
before described. The line K indicates the communication with the lighting bobbin
herein-after referred to.
The improved manipulator by the aid of which the direction of the current is
controlled, is shewn in Figures 8 and 9. It consists of two insulating handles P, Q,
Figuro 9, each corresponding with one of the two screws D and D¹ of the lamp
secured to an insulating plate Q¹. The handle P carries two sets of springs insulated
from one another. Upon the insulating plate Q₁ there are provided four contact
points, a, b, c, d, which are in communication with the binding screws indicated by
the same letters in Figure 5, and which serve to actuate the upper carbon holder E,
for example, in the lamp. By the side of each of these contact points there is situate
a contact maker, indicated by a black dot in the Drawing, Figure 9, and the whole

page_text: are arranged in such a manner that the springs of the handle P place them in com-
munication two by two.
The two contact makers, shewn by black dots in Figure 9, which communicate
with a and o, are in communication with a contact plate R. In like manner the
two other alternate contact points b and d are placed in communication with a con-
tact plate S.
The two contact plates R and S are arranged in such a manner that by passing
a metallic bruslı M, Figure 5, over them in the direction of the arrow, the necessary
conditions will be fulfilled.
The insulating plate Q1 is also provided with a pair of contact plates, T, U, which
aro placed by the aid of the handle Q in communication with contact points e, f, g,
h, serving in like manner to impart motion to the lower carbon holder E¹.
It is evident that the parts being arranged in this manner and the proper com-
munications established, it will be simply necessary before making the contact with
the brush M in order to produce the desired effect in the lamp to place the handles
in the following positions, videlicet :-
To turn the handle P/ upwards.
In order to cause the \
"
"
(downwards.
cend.
In order to lower
into an inter- In order to stop
mediate posi-
tion.
by touching the
contact plates T, U,
with M.
and to combine these motions in order to obtain all the effects desired
The light may be produced by means of the herein-before described apparatus in
the following manner :-
First. The carbons are placed in contact by bringing one of them near to the
other by the aid of the said apparatus; at the moment when they come into contact
notice is given of the same either by an indicating needle V shewn in the Drawing,
Figure 8, or by a platinum wire which becomes heated to redness.
Secondly. As soon as this indication is given, the operator by effecting a single
contact, causes the carbons to be drawn a short distance apart.
Thirdly. The lighting bobbin is next worked, which bobbin is fixed to the
lower carbon holder, and causes a sufficient vibration to produce the contact, and
immediately afterwards the separation. The lighting takes place instantaneously.
These precautions are not necessary except for the first lighting; for the successive
operations of lighting the carbons will be already separated, it is simply necessary
to work the lighting bobbins.
This lighting bobbin, which is represented in Figure 7, consists simply of a bobbin
8 secured firmly to the lower carbon holder E¹, and acting under the influence of
the same auxiliary current as serves for the other movements. When it commences
to move its vibrations are communicated to the lower carbon, and if this latter
should happen to be situate in close proximity to the upper carbon a contact ensues,
followed by the recoil necessary to the instantaneous formation of the arc, and the
illumination is produced. The position of the lighting contact point is indicated
at Z, and the position of the extinguishing contact points at X, Y, Figures 8 and 9.
The lamp as shewn in Figures 1 and 2 is completely enveloped in a case 9 pro-
vided at its central portion with an optical arrangement H, at the centre of which
the light of the lamp should flash. The mechanism of the electro-magnets, the levers,

page_text: ratchet wheels, pawls, and all other necessary working parts are likewise enclosed
in a case I, which entirely protects them from all external shocks.
Figure 10 represents an arrangement whereby the carbons may be brought
together automatically, so as to maintain them at the required distance, notwith-
standing the constant wear to which they are subjected. The apparatus consists of
a clockwork motion I¹, the speed of which may be readily adjusted by means of a
key or of a button, and which serves to maintain in uniform motion a metallic brush
or rubber J performing the functions of the frictional contact maker M hercin-before
referred to. In this case the contact points a, b, c, d, are to be disposed upon a
vertical board K fitted to the fixed table which is placed under the hand of the
operator, they are moreover arranged around the centre of rotation of the clockwork
motion in such a manner that the contact-making brush passes over then con-
tinually in the order required for causing the carbons to approach one another
constantly, in proportion as they become worn.
Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,―
First. The general arrangement and combination of apparatus employed for and
in connection with the production of electric light for signalling and other purposes,
substantially as herein-before described and illustrated by the accompanying
Drawings
Secondly. The employment of one or more auxiliary currents derived from the
source of light, or otherwise, and not necessarily acting under the influence of the
illuminating or lighting current for the purpose of effecting the lighting and extin-
guishing of the lamp and the focussing or adjustment of the carbons or electrodes,
substantially as herein-before described
Thirdly. Arranging and combining (at any required distance from the lamp, but
within the range of the attendant working the signals), the whole of the means or
appliances necessary for enabling the lighting and extinguishing to be effected in-
stantaneously and the position of the carbons or electrodes to be adjusted, and
especially for enabling the light to be brought to and maintained at the optical
centre of the lamp, even in the case of a breakage, of the carbons or electrodes, and
thereby dispensing with all delicate mechanism liable to become deranged withiņ
the body of the lamp substantially as herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my
Specification set my hand and seal, the Twenty-second day of February, One
thousand eight hundred and seventy-seven.
J. HENRY JOHNSON. (L.S.)