Year: 1896

page_text: Date of Application, 17th Nov., 1896
Complete Specification Left, 17th Aug., 1897-Accepted, 18th Sept., 1897
We ALEXANDER BEWICKE BLACKBURN of Bushbury Works Wolverhampton in tho
County of Stafford Civil Engineer and GEORGE WILLIAM FAIRALL of 34 Ann Street
Tettenhall Road Wolverhampton aforesaid, Electrician, do hereby declare the nature
of this Invention to be as follows:-
This Invention relates to electric arc lamps working with either single or double
carbons and with either direct or alternating current.
The brake wheel is provided with ratchet teeth as well as with a plain or grooved
periphery to which the brake block is applied. A pawl engages with the said ratchet
teeth and the brake block is mounted on the same axle as the pawl or it can be
centred on any convenient part of the pawl or of a tail piece with which the pawl is
provided. The said brake block has a bracket at bottom upon which one end of a
spiral or other spring bears, the other end of the said spring bearing on the tail
piece of the pawl in such a manner as to limit the travel of the brake block and
maiutain it, in contact with the brake wheel both when the pawl is engaged with and
disengaged from the ratchet teeth. For raising and lowering the carbons an endless
chain (or the like) is used the slide rods carrying the carbons forming practically a
part of the chain or the like. The said chain or the like runs on sprocket wheels
above and below. When a current is passing a core piece is so attracted by a coil
that by a chain or the like to which it is attached to the tail piece of the pawl it
engages the pawl with the ratchet teeth on the brake wheel as hereinafter described.
There is a pinion fixed to the axis of the brake wheel which gears with a toothed
wheel carrying a drum for paying out or winding in a metallic tape or cord to carry
current to one of the carbon holders. This toothed wheel engages with a second
toothed wheel which has fixed to its axis the upper sprocket wheel over which the
chain or the like controlling the carbon bolders passes. The aforesaid pawl, and the
frame carrying the brake wheel and pinion have their bearing on the axle of
the drum wheel. When the aforesaid core is attracted by the a coil it causes the pawl
to be pressed against the matchet teeth on the brake wheel and on moving further the
frame of the brake block to which the pawl is attached moves on its axis moving the
drum and sprocket wheel aforesaid with it through a small space thus separating
the carbon holders and striking the arc. When the resistance of the are becomes
too great the frame of the brake block returns to its original position and rests
against a stop provided for it. The pawl then leaves the ratchet teeth of the brake
wheel and the latter is free to revolve but a coustant and steady motion is maintained
through the pressure of the brake block upon the brake wheel. The lower sprocket
wheel over which the chain or the like which connects the two carbon holder slides
is supported by a depending piece carried by parallel tubes or rods attached to the
base of the casing of the mechanism in line with the sprocket wheel above. The
said tubes or rods form a guide for the carbon holder slides and if tubes be used with
the slides inside, the said tubes may be slotted to allow the projecting.arins from the

page_text: slides to move up and down. For lamps having double carbons duplicate parts may
be used and for lamps of the inverted type four sprocket wheels are preferably used
and the tubes or rods which guide the carbon holder slides are set at a greater
distance apart and are connected by end pieces to suspend the lamp.
1000
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
We, ALEXANDER BEWICKE BLACKBURN of Bushbury Works, Wolverhampton, in the
County of Stafford, Civil Engineer, and GEORGE WILLIAM FAIRALL, of 34 Ann Street
Tettenhall Road, Wolverhampton, aforesaid 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 :-
This Invention relates to electric arc lamps working with either single or double
carbons aud with either direct or alternating current.
We will describe the invention with reference to the accompanying dmwings.
Figures 1 and 2 representing elevations at right angles to each other and
Figure 3 an elevation of the opposite side to that shewn in Figure 2 of so much of
a lamp as is necessary to illustrate the invention one of the solenoid coils being
removed in Fig. 1 to shew more clearly the gear for operating the electrodes.
The brake wheel A is provided with ratchet teeth as well as with plain or grooved
parts of its periphery at a to which the brake block B is applied. A pawl C engages
with the said ratchet teeth and the brake block B is carried by the lever bracket b
which is mounted on the same axle b as the pawl C, or it can be centered on any
convenient part of the pawl or of the tail pieco c with which the said pawl is provided.
One end of the spring D bears on a projection b³ from the bracket b the other end of
the said spring bearing on the tail piece c of the pawl in such a manner as to limit
the travel of the brake block and maintain it in contact with plain or groove parts
of the periphery of the brake wheel both when the pawl C is engaged with and
disengaged from the ratchet teeth a. For raising and lowering the carbons E an
endless chain F (or the like) is used, the slide rods e and arms e2 carrying the carbon
holders forming practically a part of the chain For the like. The said chain For
the like runs on sprocket wheels G above and below, the upper sprocket wheel being
carried on a centre mounted in bearings in standards g secured to the base plate of
the casing of the mechanism and the lower sprocket wheel being mounted on a
centre mounted in bearings in a casing g² secured to the tubes H in which the
chain F and rods e run, the said tubes being also connected to the base of the casing
of the mechanism. When a current is passing through the lamp a core piece I is so
attracted by a coil I' that it operates a lever J centred at j which by the connection
attached to it and to the tail piece c of the pawl C causes the said pawl to engage
with the ratchet teeth a on the brake wheel A as hereinafter described. There is a
pinion L fixed to the axis of the brake wheel A which pinion gears with a toothed
wheel M which is fixed to the same axis as the upper sprocket wheel G over which
the chain F or the like controlling the carbon holders passes.
Flexible conductors suitably connected carry current to the carbon holders. The
frame A carrying the brake wheel A pinion I. and pawl C has its bearing on the same
axle as the toothed wheel M and upper sprocket wheel G. When the aforesaid core I
is attracted by a coil Is it causes the pawl C to be pressed against and engage with

page_text: the ratchet teeth on the brake wheel A and on moving further, the frame A', of
the brake wheel A, to which the pawl C is attached, moves on its axis, moving the
upper sprocket wheel G with it through a small space thus scparating the carbons
and striking the arc. When the resistance of the arc becomes too great and the coil I'
releases the core I the frame A returns to its original position and its turned down
end A³ rests against a stop N on the base of the casing of the mechanism. The pawl C
then leaves the ratchet teeth of the brake wheel A and the said brake wheel is free
to revolve to feed the carbons by the pinion L engaging with the wheel M a constant
and steady motion being maintained by reason of the pressure of the brake block B
upon the brake wheel A.
The tubes H and rods e form guides for the carbon holder slides the said tubes
being slotted to allow the projecting arms from the rods e to move up and down. For
lamps having double carbons duplicate parts may be used and for lamps of the inverted
type the arrangement can be inverted.
The arrangement illustrated is one of the differential type but the invention it will
be evident can be applied to lamps of other type.
Having now particularly described and ascertained the nature of this inveni-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In an electric arc lamp the arrangement for controlling the carbon holders by an
endless chain or the like substantially as herein before described.
2. In an electric are lamp a brake wheel with a periphery which is in part plain
and partly provided with ratchet teeth and a brake block and pawl for acting on the
plain and ratchet toothed parts of the periphery respectively substantially as herein-
before described.
3. In an electric arc lamp the combination of a moveable framework carrying a
pawl and a brake block for acting upon a brake wheel with a periphery partly toothed
for the pawl and partly plain or grooved for the brake block and operated substantially
as hereinbefore described.
4. In an electric arc lamp a brake block provided with a tail piece and a spring
situated between the tail piece and brake block substantially as herein before
described.
5. The arrangement constituting regulating mecbanism for are electric lainpa
substantially as hereinbefore described aud illustrated in the accompanying drawings.
Dated this 17th day of August 1897.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents..