Year: 1886

page_text: I, JOHN ROPER of Trafalgar Street, Bradford in the County of York, Electrician,
do hereby declare the nature of the above named invention to be as follows:-
My improvements consist of appliances which steady the descent of the rod, to
which the upper Carbon holder of arc lamps is attached, or a modification of the
same apparatus would steady the ascent of the rod to which the lower carbon
holder is attached, in lamps where the upper carbon remains stationary, thereby
causing the light to be uniform and steady, and avoiding the jumping or flashing
of the light.
To carry out my invention, I attach to a loop or stud, fixed to the lower part of
the rod which carries the upper carbon holder, a cord, which cord passes over a
grooved pulley supported in bearings upon brackets projecting from the vertical
frame which acts as a guide to the rod of the carbon holder. One end of the cord
is fastened to the periphery of the pulley, so that any descent of the rod causes a
corresponding revolution of the pulley.
Upon the same axle as the pulley herein before mentioned, is fixed a smaller
pulley, which also has a cord passing over it, and fixed to its periphery, and at the
other end of this cord is suspended a long narrow cylinder, weighted at its lower
part, to partially counterpoise the weight of the rod carrying the carbon holder,
and this cylinder is maintained in a vertical position, parallel with the rod, by
means of guide rods passing through lugs at the sides of the cylinder. A vertical
piston rod fixed to the under side of the bracket which supports the axle of the
two pulleys, herein before mentioned, has fixed to its lower extremity a piston,
which fits easily into the cylinder, and the cylinder is partially filled with
glycerine, or other suitable liquid, which does not easily evaporate.
When the rod which carries the carbon holder is partially liberated, by the
clutch, actuated by an electro magnet in the usual manner, the weight of the
rod actuates the cord passing over the larger pulley herein before referred to, and
the motion thereby caused, is transmitted to the smaller pulley fixed upon the
same axle.
This smaller pulley is prevented from revolving suddenly, as the glycerine
contained in the cylinder suspended from the pulley must pass gently upwards,
past the edges of the piston, whereby the cord passing over the smaller pulley is

page_text: kept at a constant and steady tension, and only passes round the smaller pulley as
the glycerine escapes past the piston in the cylinder.
By this arrangement, no jerking or sudden drop of the rod carrying the carbon
holder is possible, and a steady light is maintained.
Instead of the cord and pulley arrangement, for steadying the rod, previously
described, one side of the rod may be formed as a rack, and the pulley may be
replaced by a toothed wheel or pinion, gearing into the rack, or the clutch, which
supports, or releases the rod, and is actuated by an electro magnet, may be dispensed
with, and in place thereof, the toothed wheel geared into the rack upon the rod
supporting the carbon holder, may be controlled by a pawl and ratchet wheel, the
pawl of which is disengaged by the action of an electro-magnet, and thereby allows
the rod to fall, or slide down the necessary distance, but is steadied in its descent
by means of the glycerine cylinder hereinbefore referred to,

page_text: I, JOHN ROPER of Trafalgar Street, Bradford in the County of York, 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 improvements consist of appliances which steady the descent of the rod to
which the upper carbon holder of arc lamps is attached or a modification of the
same apparatus would steady the ascent of the rod to which the lower carbon
holder is attached, in lamps wherein the upper carbon remains stationary, thereby
causing the light to be uniform and steady and avoiding the jumping or flashing
of the light.
To carry out my invention, I attach to a loop or stud fixed to the lower part
of the rod which carries the upper carbon holder a cord, which cord passes over a
grooved pulley supported in bearings upon brackets projecting from the vertical
frame which acts as a guide to the rod of the carbon holder. One end of the cord
is fastened to the periphery of the pulley, so that any descent of the rod causes a
corresponding revolution of the pulley.
Upon the same axle as the pulley hereinbefore mentioned, is fixed a smaller
pulley which also has a cord passing over it and fixed to its periphery, and at the
other end of this cord is suspended a long narrow cylinder weighted at its lower
part to partially counterpoise the weight of the rod carrying the carbon holder and
this cylinder is maintained in a vertical position parallel with the rod by means
of guide rods passing through lugs at the sides of the cylinder. A vertical piston
rod fixed to the underside of the bracket which supports the axles of the two pulleys
herein before mentioned has fixed to its lower extremity a piston which fits, easily
into the cylinder and the cylinder is partially filled with glycerine or other suitable
liquid which does not easily evaporate.
When the rod which carries the carbon holder is partially liberated by the clutch
actuated by an electro-magnet in the usual manner the weight of the rod actuates
the cord passing over the larger pulley herein before referred to, and the motion
thereby caused is transmitted to the smaller pulley fixed upon the same axle.
This smaller pulley is prevented from revolving suddenly as the glycerine
contained in the cylinder suspended from the pulley must pass gently upwards
past the edges of the piston whereby the cord passing over the smaller pulley is
kept at a steady and constant tension and only passes round the smaller pulley as
the glycerine escapes past the piston in the cylinder.
By this arrangement no jerking or sudden drop of the rod carrying the carbon
holder is possible and a steady light is maintained.
Instead of the cord and pulley arrangement previously described one side of the
rod may be formed as a rack and the pulley may be replaced by a toothed wheel
or pinion gearing into the rack, or the clutch which supports or releases the rod,
and is actuated by an electro-magnet, may be dispensed with and in place thereof
the toothed wheel geared into the rack upon the rod supporting the carbon holder
may be controlled by means of a pawl and ratchet wheel, the pawl of which is
disengaged by the action of an electro-magnet and thereby allows the rod to fall
or slide down the necessary distance, but is steadied in its descent by means of
the glycerine cylinder herein before referred to.
In order to enable my invention to be fully understood I will proceed to describe
the same with reference to the accompanying drawings in which figure 1 repre-

page_text: sents a front elevation of an electric arc lamp to which my improvements are
applied, and figure 2 represents a side elevation of the same. Figures 3 and 4
represent plans of the same partly in section at the lines a and b respectively.
In figure 1 a portion of the spiral conducting wire P¹ is omitted for the sake of
convenience.
The upper carbon holder B is carried by the rod J which passes through the
centre of the base-plate D¹ and is guided by the short tube C¹, through which tube
the rod has free vertical action but is steadied laterally. The rod J is supported
by the cord or wire H which is by preference fixed to the lower portion of the rod
or to the upper carbon holder B. The upper portion of the cord H is carried over
and fixed in the groove of the larger pulley D so that any upward or downward
motion of the rod J causes a corresponding revolution of the wheel D and also of
the smaller wheel E which is fixed upon the same axis.
In the groove of the smaller pulley E is placed, and secured by one of its ends,
the cord C, which is attached to and supports the glycerine cylinder G. This
cylinder is steadied by the guide rods G¹ and is weighted at K so as to nearly
counterpoise the weight of the rod J with its carbon-holder.
A fixed vertical piston rod H¹ is attached to the bracket F, which piston rod
carries at its lower extremity a piston fitting easily in the glycerine-cylinder G.
The switch Y is for the purpose of completing or breaking the current.
The current for supplying the upper carbon from the binding screw Q, passes
along the spiral conducting wire P¹ to the rod R, from whence it passes along the
wire A¹ and through the coils of the electro-magnet P which magnet works the
clutch O.
The current after passing through the coils of the magnet, is carried to the rod J
by means of the clutch and the wire brush F which ensures perfect but easy
sliding contact. The rod J then conducts the current to the upper carbon
holder B.
The current for supplying the bottom carbon holder passes from the binding
screw X along the spiral conducting wire V to the metallic rod W, along the
wire B¹, through the base plate D¹ (from which it is properly insulated) and down
one of the stays S to the bottom carbon holder T.
As a slight modification of the apparatus hereinbefore described the glycerine
cylinder may be fixed and the piston may be moveable.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :-
1. In an electric arc lamp, the moveable cylinder with fixed piston-rod and easily
fitting piston, the cylinder being isolated from the carbon holder-rod and partly
filled with glycerine or other suitable liquid, which acts as a resistance to any
sudden fall of the carbon holder, and thereby prevents unsteadiness or jumping of
the light all in the manner substantially as described and represented in the
accompanying drawings.
2. A modification of claim 1 whereby I make use of a fixed cylinder and a
moveable piston and piston rod, thereby effecting the same result.
1000
WM JAS. BAKER,
Town Hall Chambers, Bradford,
Agent for the Applicant.