Year: 1895

page_text: Date of Application, 11th Feb., 1895
Complete Specification Left, 11th Nov., 1895-Accepted, 14th Dec., 1895
I, WILLIAM ERNEST BURNAND, of 31 Edgehill Road, Netheredge, Sheffield,
in the County of Yorkshire, Electrician, do hereby declare the nature of this
invention to be as follows:-
My invention relates to improvements in electric are lamps by which certain
advantages are obtained.
In carrying my invention into effect I employ a cap or cover to which the
several parts are attached and at a suitable distance below the said cap or cover
and supported therefrom by any suitable means such for example as a casing
place a reflector designed to throw the light chiefly downwards. The mechanism
of the lamp is contained in the space between the said cap or cover and the said
reflector. Projecting downwards from the cap are two guides or sets of guides for
sustaining the carbons or the carbon holders. The said guides are so placed that
the carbons, the lower ends of which pass through orifices in the reflector, meet
at an angle, say of 90 degrees or thereabouts, a short distance below the reflector.
From the carbon holders or clamps chains or cords pass over pulleys to a drum
or pair of drums mounted on the same shaft as a wheel hereinafter termed the
brake wheel. The said brake wheel is smooth or grooved at one side of its
periphery and furnished with teeth or projections at the other side of its periphery.
A suitably formed lever is pivoted in a position eccentric to the said brake
wheel. To one end of this lever is articulated one end of a brake piece at the
other end of which is a brake block serving to bear against the smooth or grooved
part of the periphery of the wheel. The brake piece has also a pin or the like
projecting therefrom and adapted to engage the teeth on the other part of the
periphery of the said wheel. To the other end of the lever I may attach a piece
of soft iron to serve as a core for a solenoid arranged in series with the carbons.
The parts are so arranged that when the said core is attracted the aforesaid pin
will engage the teeth of the brake wheel and move it and the drum through a
certain angular distance whilst when the attraction is diminished gravity will
move the lever in the opposite direction release the pin from engagement with
the teeth and subsequently remove the brake block from the smooth part of the
brake wheel such action being facilitated and or controlled by a spring and a stop
placed close to the articulation of the lever with the brake piece.
The action of my invention is as follows. When the lamp is trimmed for use
the carbons come together by gravity. The current then being turned on and
the solenoid being in series with the carbons the core is attracted the lever
moved the pin brought into engagement with the teeth of the brake wheel and the
latter moved angularly through a definite distance. The drum or drums on
which the chains or cords are wound being fixed on the same shaft as the brake
wheel is or are also moved angularly so as to wind up the said chains or cords to
a definite extent pull the carbons apart and thus strike the arc. As the carbons
burn away the resistance of the are increases less current passes through the
solenoid and the core is released to a certain extent. The pin is then removed
from engagement with the teeth of the brake wheel but until still further
movement takes place caused by still further diminution of attraction the brake
block still presses against the smooth or grooved part of the brake wheel until the

page_text: ɛaid brake wheel is by release of the pin and or of the brake block free to move
so that the weight of the carbons shall unwind some of the chain or cord from the
drum or drums and allow of the carbons approaching one another when more
current will now traverse the solenoid and the same cycle of operations be
repeated.
My invention is applicable either to continuous or alternating currents.
Dated this 11th day of February 1895.
1, WILLIAM ERNEST BURNAND, of 31 Edgehill Road, Netheredge, Sheffield,
in the County of Yorkshire, Electrician, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
My invention relates to improvements in electric are lamps by means of which
certain advantages are obtained.
In order that my invention may be readily understood 1 shall proceed to
describe it with reference to the accompanying drawings in which similar parts are
indicated by similar letters of reference.
In the said drawings,
Figure 1 is a diagrammatic view of one form of my complete lamp, the cover,
casing, globe and reflector being shown in section and the working parts of the
lamp in elevation.
Figure 2 is a cross section of a form of brake wheel. Figure 3 is a cross
section of another form of brake wheel, which differs from that shown in Figure 2
in that a part of the brake wheel is grooved instead of plain or smooth.
Figure 4 is a diagrammatic elevation showing the brake piece and part of the
brake wheel with these parts in such position that the pin on the brake block is
engaging the teeth and the brake block is pressing on the wheel. Figure 5
shows such engagement by a cross section of the parts.
Figure 6 is a diagrammatic elevation and Figure 7 a cross section of the same
parts seen when the pin no longer engages the teeth but when the brake bluck
still presses on the wheel.
Figures 8 and 9 show in elevation and in cross section respectively the same
parts with neither the pin nor the brake block touching the wheel.
Figure 10 is a cross section of the carbons and guides near the lower extremities
of the latter.
Referring now to the figures I employ a cap or cover A to to which the several
parts are attached and at a suitable distance below the said cap or cover, and
supported therefrom by any suitable means, such for example as a casing B,
I place a reflector C designed to throw the light chiefly downwards. The
mechanism of the lamp is contained in the space between the said cap or cover
and the said reflector. Projecting downwards and inwards from the said cap are
two guides or pairs of guides D, D for sustaining the carbons E, E or the carbon
holders F, F. These guides are so placed that the carbons, the lower ends of
which pass through orifices c, c in the reflector, meet at an angle, say of 90 degrees
or thereabouts, a short distance below the reflector. From the carbon holders
chains or cords pass over pulleys H, H to a drum J (or pair of drums) mounted

page_text: on the same shaft as a wheel K hereinafter termed the brake-wheel. This brake
wheel is smooth (see Figure 2) or grooved (see Figure 3) at one side k of its
periphery and furnished with teeth or projections at the other side k¹ of its
periphery. A suitably formed lever L is pivotted at in a position eccentric to
the said brake wheel. To one end of this lever is articulated at m one end of a
brake-piece M at the other end of which is a brake-block m¹ serving to bear
against the smooth or grooved part of the periphery of the brake wheel. The
brake piece has also a pin m² or the like projecting therefrom and adapted to
engage the teeth on the other part of the periphery of the said wheel. To the
other end of the lever I attach a piece of soft iron n to serve as a core for a
solenoid N arranged in series with the carbons. The parts are so arranged that
when the said core is attracted the aforesaid pin will engage the teeth of the
brake wheel and move it and the drum through a certain angular distance whilst
when the attraction is diminished gravity will move the lever in the opposite
direction release the pin from engagement with the teeth and subsequently remove
the brake wheel from the smooth or grooved part of the brake wheel such action
being facilitated and or controlled by a spring P and a stop Q placed close to the
articulation of the lever with the brake piere.
It will be noticed that in Figure 6 I have shown a slightly modified form of
device for removing the brake block from the brake wheel. In this case a small
lug m³ projects trom the brake block and on one side of this is a recess m¹ into
which the end of the stop rod Q enters. It will be seen that the brake block
continues to press upon the wheel until the stop rod and the outer edge or surface m
of the recess m¹ come in contact when further movement due to further decrease of
current removes the brake block from contact with the brake wheel.
The action of my invention is as follows. When the lamp is trimmed for use
the carbons come together by gravity. The current then being turned on and the
solenoid being in series with the carbons the core is attracted the lever moved
the pin brought into engagement with the teeth of the brake wheel and the latter
moved angularly through a definite distance. The drum or drums on which the
chains or cords are wound being fixed on the same shaft as the brake wheel is or
are also moved angularly so as to wind up the said chains or cords to a definite
extent pull the carbons apart and thus strike the arc. The brake is now in the
position shown in Figures 4 and 5. As the carbons burn away the resistance of
the arc increases less current passes through the solenoid and the core is released
to a certain extent. The pin is then removed from engagement with the teeth of
the brake wheel and the parts take the position shown in Figures 6 and 7, but
until still further movement takes place caused by still further diminution of
attraction the brake block still presses against the smooth or grooved part of the
brake wheel until the said brake wheel is by release of the pin and of the brake
block as shown in Figures 8 and 9 free to move so that the weight of the carbons
shall unwind some of the chain or cord from the drum or drums and allow of the
carbons approaching one another when more current will now traverse the solenoid
and the same cycle of operations be repeated.
My invention is applicable either to continuous or alternating currents.
For
I desire it to be understood that I do not limit myself to the specific form of my
invention hereinbefore set forth, as, the principles of the invention being under-
stood, the details of construction may be varied to an indefinite extent.
example although I have shown the sclenoid N in series with the carbons it
is obvious that I may place it in a shunt to the are circuit or give it a
differential winding. Any competent engineer will know how to modify the
details of the lamp to suit particular applications, or installations.
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 The
Lination of note substantialle or not forth
:

page_text: 2. The means for striking the arc and controlling the feed of the carbons,
substantially as set forth.
3. The combination of inclined carbons (with or without guides) reflector
through which the said carbons pass and regulating mechanism, substantially as
set forth.
For the Applicant,
J. G. LORRAIN, M.I.E.E., M.I. Mech. E.,
Norfolk House, Norfolk Street, Strand, London, W.C.,
Chartered Patent Agent.