Improvements in Electric Search Lights and in Mechanism for Feeding the Carbons.
Year: 1890

page_text: Date of Application, 3rd July, 1890
Complete Specification Left, 23rd Mar., 1891-Accepted, 2nd May, 1891
PROVISIONAL SPECIFICATION.
Improvements in Electric Search Lights and in Mechanism for
Feeding the Carbons.
1, HERBERT JOHN ALLISON, of 52 Chancery Lane, London, in the County of
Middlesex, Patent Agent, do hereby declare the nature of this invention which
has been communicated to me from abroad by Barton B. Ward, of the City, County
and State of New York, Electrical Engineer, to be as follows:
This invention relates to the manner of mounting the electric arc light, used for
a search or focusing lamp, so that the lamp may be turned in either a horizontal or
a vertical plane to throw the beam of light in any desired direction.
The invention relates further to the construction of the regulating mechanism
for feeding the carbon pencil of the arc light.
In order to provide for tilting and turning the projector from a
position beneath
its base, I mount the reflector and are lamp in a frame work consisting preferably.
of a protecting cylinder, and pivot such cylinder or frame work in a U shaped
frame so that it may be free to swing in a plane at right angles to the base. The
U shaped frame is fastened to the top of a turning shaft mounted in a vertical line
and adapted to be rotated in a suitable base piece or standard for which purpose
the vertical shaft is, at a point below the base plate, provided with a handle or arm.
The shaft is hollow. Devices for rotating the frame carrying the reflector extend
through said hollow vertical shaft. These devices may be of any suitable
character, as for instance, cords running over pulleys and connected to the frame,
or the device may be composed of an interior shaft which turns within the vertical
shaft and by means of a bevelled gear communicates motion to a horizontal shaft
which in turn is connected by a belt with a wheel fixed on the journal of the
frame carrying the arc lamp and reflector so that the whole may be tilted in a
vertical plane.
The focusing lamp in such frame is constructed so that the tendency of the
carbons to feed together will be the same in all positions of adjustment in a vertical
plane from horizontal to vertical position. For this purpose I balance the weight
of the carbon carrying rods or racks against one another making their weights
approximately equal. The rack which supports the upper carbon extends through
the frame work of the lamp mechanism and has a horizontal arm which carries the
upper carbon carrier over the lower carbon. The two rods supporting the carbon
are connected together by means of two pulleys or wheels one twice the circum-
ference of the other and fixed upon the same shaft. Cords connect the lower ends
of the rack rods to the said wheels and are wound upon them so that the carbons
will feed at the proper relative movement to keep the arc at the focus of the
reflector. The carbons are moved towards one another by means of a supplemental
weight which is suspended from a cord passing over a pulley and wound upon a
drum. This drum is upon a shaft carrying a second drum or wheel upon which is
wound a cord connected to one of the carbon carriers in such manner that the
weight shall tend to pull the carbons together. The two drums are of different
sizes so that a relatively small movement of the weight may be required to
produce the desired movement of the carbon carriers.
The feed of the carbons is controlled and the formation of the arc is produced by
means of a pivoted lever carrying a train of wheels which gears with one of the
carbon carriers, as for instance that carrying the upper carbon, and supports the
armature or core for an electro magnet. The train of wheels carries a detent or
escapement wheel, and a suitable stop is provided to be engaged by said escapement
wheel when the electro magnet pulls down one end of the frame. These parts are

page_text: arranged as ordinarily in electric arc lamps so that the train will be held from
movement so long as the arc is of the proper length, but when the arc lengthens by
consumption of the carbons, the magnet loses its power and the retractor applied
to the frame carrying the train of wheels moves the escapement wheel away
from the stop and the frame may then rotate thus permitting the carbon rod or
carrier to be moved by the supplemental weight so as to bring the carbons nearer
together. A suitable spring is provided to move the frame carrying the train of
wheels and disengage the escapement wheel.
Dated this Third day of July A.D. 1890.
ALLISON BROS.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Electric Search Lights and in Mechanism for
Feeding the Carbons.
1, HERBERT JOHN ALLISON, of 52 Chancery Lane, London, in the County of
Middlesex, Patent Agent, do hereby declare the nature of this invention (which
has been communicated to me from abroad by Barton Brewer Ward, of 18 Cortland
Street, City, County and State of New York, Electrical Engineer,) to be particu-
larly described and ascertained in and by the following statement:-
This invention relates to the manner of mounting the electric arc light, used for
a search or focusing lamp, so that the lamp may be turned in either a horizontal or
a vertical plane to throw the beam of light in any desired direction.
The invention relates further to the construction of the regulating mechanism for
feeding the carbon pencil of the arc light.
In order to provide for tilting and turning the projector from a position beneath
its base, I mount the reflector and are lamp in a frame work consisting preferably
of a protecting cylinder, and pivot such cylinder or frame work in a U-shaped frame
so that it may be free to swing in a plane at right angles to the base. The
U-shaped frame is fastened to the top of a turning shaft mounted in a vertical
plane and adapted to be rotated in a suitable base piece or standard for which
purpose the vertical shaft is, at a point below the base plate, provided with a handle
or arm. The shaft is hollow. Devices for rotating the frame carrying the reflector
extend through said hollow vertical shaft. These devices may be of any suitable
character, as for instance, cords running over pulleys and connected to the frame,
or the device may be composed of an interior shaft which turns within the vertical
shaft and by means of a bevelled gear communicates motion to a horizontal shaft.
which in turn is connected by a belt with a wheel fixed on the journal of the frame
carrying the arc lamp and reflector so that the whole may be tilted in a vertical
plane.
The focusing lamp in such frame is constructed so that the tendency of the
carbons to feed together will be the same in all positions of adjustment in a vertical
plane from horizontal to vertical position. For this purpose I balance the weight
of the carbon carrying rods or racks against one another making their weights
approximately equal. The rack which supports the upper carbon extends through
the frame work of the lamp mechanism and has a horizontal arm which carries the
upper carbon carrier over the lower carbon. The two rods supporting the carbon
are connected together by means of two pulleys or wheels one twice the circum-
ference of the other and fixed upon the same shaft. Cords connect the lower ends
of the rack rods to the said wheels and are wound upon them so that the carbons
will feed at the proper relative movement to keep the are at the focus of the
reflector. The carbons are moved towards one another by means of a supplemental
weight which is suspended from a cord passing over a pulley and wound upon a
drum. This drum is upon a shaft carrying a second drum or wheel upon which is
wound a cord connected to one of the carbon carriers in such manner that the

page_text: weight will tend to pull the carbons together. The two drums are of different
sizes so that a relatively small movement of the weight may be required to produce
the desired movement of the carbon carriers.
The feed of the carbons is controlled and the formation of the arc is produced by
means of a pivoted lever carrying a train of wheels which gears with one of the
carbon carriers, as for instance that carrying the upper carbon, and supports the.
armature or core for an electro magnet. The train of wheels carries a detent or
escapement wheel, and a suitable stop is provided to be engaged by said escapement
wheel when the electro magnet pulls down the frame. These parts are arranged as
ordinarily in electric arc lamps so that the train will be held from movement so long
as the arc is of the proper length, but when the arc lengthens by consumption of
the carbons, the magnet loses its power and the retracting spring applied to the
frame carrying the train of wheels causes the escapement wheel to be disengaged
from the stop and the frame may then rotate thus permitting the carbon rod or
carrier to be moved by the supplemental weight so as to bring the carbons nearer
together.
In the accompanying drawings:
:-
Fig. 1, is a vertical central section through the casing or frame containing the
lamp and reflector and through the upper portion of the mechanism for turning said
lamp and reflector horizontally and vertically.
Fig. 2, is a front elevation of the apparatus.
Fig. 3, is a cross section through a part of the supporting frame.
Fig. 4, is a side view of a part of the mechanism.
Fig. 5, is a side elevation of the mechanism for feeding the carbons.
Fig. 6, is an end elevation of the devices employed for furnishing the power to
feed the carbons together.
C2, is a projecting cylinder or frame which carries the lamp F, and reflector D.
The carbons of the lamp between which the arc is produced are indicated at E, E¹.
The cylinder is provided with doors or caps at each end and with upper and lower
projections j, k, provided with caps,k. The projecting cylinder or frame-
work C, is mounted in a U-shaped frame or support A, in such manner that it
shall be capable of turning in a horizontal plane therein.
For this purpose it is
suitably pivoted at points b. B, is a standard or support upon which the frame A,
is properly mounted so as to be capable of turning in a horizontal plane or plane
at right angles to that in which the cylinder carrying the lamp and reflector may
turn.
Attached to the frame A, and extending down through the standard or support B,
and through the floor or base G, on which said, standard is mounted, is a standard
shaft H, which may be rotated by means of a wheel H2, or other device, so as to
turn the frame A, and supported lamp or reflector in a horizontal plane. By this
means the lamp and reflector may be located on the top of a pilot or wheel house
and the direction of the beam of light controlled by the pilot at his station beneath.
The shaft H, is hollow, as indicated, and through it extends a spindle or shaft I,
or other mechanism for turning the frame C, carrying the lamp and reflector in a
vertical plane. 12, is a handle secured to the spindle or shaft I, at its lower end.
At the upper end shaft I, is provided with a gear which gears with a wheel upon
the horizontal shaft L, mounted in bearings L2, on the frame A. A wheel M, is
secured to the shaft L, and a wheel N, is pivoted or fastened to the shaft b,
extending from the casing of the lamp and reflector and forming the axis on which
the same turns vertically. The belt Ó, connects the wheels M and N.
Electrical connection with the lamp is made in any way preferably by sliding
contacts in the form of rings carried respectively by the frame A, and the standard
or support B, and resting upon one another. Preferably these rings constitute the
bearings upon which the frame is supported and turned. Such contacts are indicated
at c, c, and d, d². The rings c, c², of copper, brass or other good conductor are let
into or supported upon a block of insulating material carried on top of standard B,
and are connected by insulated wires or conductors running through said standard or

page_text: by other means with the opposite poles of the circuit supplied from a dynamo electric
machine or other source of electric energy, indicated at K. The rings d, d², are
fixed in a block of insulating material at the bottom of the standard A, and rest
respectively on the rings c, ². Wire connections run from rings d, d², along the
groove a, on the inner side of the frame A, to the case C, at or near the pivots and
lead through the case or its pivots to the lamp within.
By means of a catch P, and connected press lever Q, supported on 12, the arm 12,
may be locked or unlocked from wheel H2, at pleasure. When locked, rotation of
the arm will simply turn the two shafts together and rotate the lamp and reflector
in a horizontal plane. When the two shafts are disengaged from one another by
pressing on K, the rotation of the arm will turn the shaft I, alone and the lamp and
reflector will be turned in a vertical plane. Any other desired means might be used
for connecting and disconnecting the two shafts at pleasure. It will be seen that by
means of wheel H2, with notches around its entire circumference adapted to be
engaged by the catch P, the operator is enabled to give the beam of light any
desired vertical inclination by turning shaft I, and then lock the two shafts together
and rotate the lamp in a horizontal plane a whole circle if desired preserving the
same vertical angle, or he may disengage the two shafts at any time, change the
vertical angle and then lock them together and continue the horizontal rotation of
the beam of light.
Instead of shaft I², cords might be extended through the said hollow shaft H, and
run over pulleys to connect with the vertically rotatable casing C, for the purpose
of changing the vertical inclination of the beam of light, the position in a horizontal
plane being changed by rotating the shaft H, as before.
The carbons E, E', are supported from the carbon carrying rods C, C¹, which
are guided and held in position by the anti-friction wheels s, supported by the frame
work or casing F of the lamp. The rod or rack C, carrying the positive carbon has
a motion downwards or towards the base of the lamp while the rod C₁, carrying the
negative carbon has a motion in the opposite direction and the proportion with
which the rods feed the carbon towards each other is controlled by the cords i, i,
attached to their lower ends and passing over the pulleys o, and o', which are
rigidly fastened together on the same shaft and supported by the frame N, fastened
to the base of the lamp and in which the shaft is free to turn; the cord i, attached
to rack C, passing over the larger wheel », and the cord i¹, attached to the rod C³,
passing over the smaller wheel o¹, by the motion of C', while travelling towards the
base of the lamp.
To accomplish the purpose of my invention it is necessary to have the rods C³,
slit or to have extra weight (not shown) added to it so that its weight with that of
its carbon will be approximately equal to that of the rod C, and its carbon.
The weight of the rod and attached carbons being balanced against one another,
as described, there will be no difference in the tendency of the carbons to feed
towards one another when the lamp is upright and when it is tilted over to an angular
position as there would be if the weight of one of said rods were depended upon to
feed the carbons, or if one of them were heavier than the other so as to have a
tendency either to feed or to separate them. As the weight of the racks or rods
and the carbons is balanced, it is also obvious that there will be no difference in the
power required to separate them in different angular positions of the lamp.
It will be seen that means must be provided to feed the carbons together as they
will stand still so far as gravity is concerned. This I accomplish by the use of some
supplemental power or force such as that of a weight W, applied so as to tend to
cause the carbons to bridge one another. The weight W, and the intermediate
mechanism connecting the same with the carbon rod C, are mounted in a frame B²,
secured to the lamp frame F, behind the rack rod C. The power of the weight W,
is communicated to the rack C, in a manner to force the same down towards the
opposite or lower carbon through wheels t, t¹, and 62, which are mounted in the
frame B2, and have cords attached to them, the cord of t, being fastened as shown
at or near the top of the rod C, while the cord of t', passes over wheel 6³, to the

page_text: weight W. The wheels t, t¹, are set in the frame B, and secured to a shaft in the
same manner as o, and o¹; the third wheel 62, being an idler over which the cord
carrying the weight W, passes; the function of weight W, being in all positions of
the lamp to cause the carbon rods to feed together forming a continual strain down-
ward on rack C.
The purpose of making the wheels t and t¹, of different diameters is to reduce
the total distance which the weight W, travels.
One of the purposes of this invention is to adapt the lamp to feed the carbons
together and maintain the arc in the proper focus while the light is being projected
in a vertical or horizontal line. It has been shown how the lamp will feed while
in a vertical position allowing the rods carrying the carbons to be balanced, and
power supplied to feed them together from other sources than gravity of the rods.
Now we will imagine the lamp turned in a horizontal position with the carbon
points uppermost; in this position it will be seen the weight of the lower rod is
subtracted, also the weight of the upper rod as is also the weight of the lamp.
magnet core of m, to be presently described, but more friction is added to the rods
in moving towards each other; this friction is about equal to the weight of the
magnet core while in a vertical position, and to further reduce this friction the
grooved wheels s, are made to entirely support and guide the square rods, thus.
reducing the friction to a minimum.
The weight W, while the lamp is in a horizontal position is free to swing out
and maintain the same strain as when in a vertical position.
In Fig. 6, the construction of the frame B2, and the arrangement of the cord in
relation to the wheels and their construction is more fully shown, the wheels t
and, being in every way like o and o¹, each wheel having its own cord and
provided with a cap v, to hold the cord in place should it be suddenly slackened.
The lamp is provided with a magnet m, around which the current passes on its.
way to the arc from generator K, connected, as already described, to the lamp in
the casing C², entering at binding post 1, thence around the magnet to the frame of
the lamp to the rack C, and across the arc to the negative rod C, which is insulated
from the frame of the lamp. From the rod C¹, it passes by a wire to the binding
post 2, and back to the generator.
As the current passes through magnet m, it attracts its core D², which is attached
by a link to the frame E², carrying a train of gearing and pivoted to the frame A²,
at F2; this train of gearing at its minimum speed end engages with rack C, while
its maximum speed end is provided with a coarse toothed wheel H³, made of magnetic
metal; this wheel is placed in near proximity to core D2, and is attracted in
proportion to the magnetic strength of core D2, which varies in proportion to the
resistance of the arc or current strength of magnet m; on top of magnet m, is a
little piece R, to lock wheel H³. The purpose of using the magnetism of wheel H,
is to reduce its motion at the time of feeding the carbons together.
The frame E, is so pivoted at F2, that as current is turned on the lamp the
core D2, is in a position to be attracted by magnet m, which motion is transmitted
through frame E2, and its gearing raising rack C, and lowering rod C¹, causing the
proper separation at the carbon points, and as the resistance increases at the arc and
less current passes, the core D2, will recede and decrease in magnetic strength and
allow wheel H³, to unlock and revolve in a direction to allow the rods C and C¹,
to feed together.
Other devices besides those shown might be employed for locking and unlocking
the shaft H, from shaft I, or other means employed for turning the lamp and
reflector in a vertical plane.
It is obvious that in place of the special form of gear train and releasing devices
for permitting a feed of the carbon rods or for moving the rods in a direction to
separate the carbons any other form of carbon separating and feed regulating
devices might be used without changing the operation of the other parts of the
apparatus, and I do not therefore limit myself to the special devices described and
shown.

page_text: Other constructions of magnet might be used in place of magnet m, and instead
of the single magnet in circuit with the arc, two magnets or coils might be employed
one in circuit with the arc and the other in a derived circuit of high resistance
around it as well understood in the art.
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:
1. In an electric search light, the combination with the lamp and reflector
mounted together on a tilting frame or casing free to swing in a vertical plane, and
a supporting frame therefor rotatable in a horizontal plane, of a hollow turning
shaft extending down from the latter through the base on which the parts are
mounted and provided with means beneath the base whereby it may be rotated,
and devices passing through said hollow shaft and mechanically connected to the
tilting frame carrying the lamp and reflector for the purpose of turning the same
in a vertical plane, as and for the purpose described.
2. The combination in a search light, of the lamp and reflector mounted together
in a hollow casing, a U-shaped frame on which the casing is pivoted to turn
vertically, a hollow shaft extending down from said U-shaped frame through the
base or support on which the said frame is mounted, an interior shaft turning within
said vertical shaft, a horizontal shaft L, geared to the same, and a belt and wheels
connecting said horizontal shaft with the pivot of the casing, as and for the purpose
described.
3. In a focusing arc lamp, carbon rods or carriers connected together by a
mechanism that would cause them to feed at the proper relative rate and having
their weights balanced against one another, as described, in combination with a
supplementary device, such as a weight, constantly connected with them for
imparting a force that will tend to feed them together with a constant power in
different positions or inclinations of the lamp.
4. The combination with the carbon carrying rods in a focusing are lamp, of the
weight W, hung from a cord which passes over a pulley wheel, and intermediate
device as described for reducing the travel of the weight as compared with that of
the carbon rod.
5. The combination in an electric arc lamp, of the carbon rods having their
weights balanced against one another and mechanically connected together so as
to feed at the same time, and the supplemental actuating weight W, attached to a
freely suspended cord passing over a pulley and connected with the upper carbon
so as to cause the latter to feed downward by the action of the weight.
་
…נו.00 .:1 ניבד
וlion.
ALLISON BROS.,
Agents for the Applicant.