Improvements in Electric Railways and Tramways.
Year: 1894

page_text: Cate of Application, 15th Mar., 1894
Complete Specification Left, 17th Dec., 1891-Accepted, 13th Apr.,
1895
PROVISIONAL SPECIFICATION.
Improvements in Electric Railways and Tramways.
WILLIAM ALDRED Brightside Bank Brightside Sheffield Engineer do hereby
declare the nature of this invention to be as follows:-
This invention relates to the improvement in the arrangement of apparatus for
the distribution of the electric current to railways and tramways and likewise
shows the means by which telephonic communication can be worked while the cars
are in motion. In the two ordinary running rails of the track, one of them is
insulated every certain number of yards from each other in sections. These
sections are composed of a certain number of rails electrically connected to each
other but insulated from the other sections at the terminations of the said sections.
The other running rail is electrically connected along its entire length and serves
as the return circuit. Down the centre of the track is placed a metallic strip or a
rail which is insulated in sections parallel and to correspond to the insulated
running rail. On the car or locomotive is placed one or several storage cells.
The main cable of the dynaino circuit is placed underground parallel to the track
and short leads from the same corresponding in number to the insulated sections
of the running rail aforesaid are brought to the magnetic switch box to be
described, and there end in a solid copper piece made taper at the end. A similar
lead is brought from each insulated section of the running rail and brought into
the magnetic switch box at the opposite end. The solid copper pieces forming
their terminations project a short distance into the inside of the box. The
magnetic switch consists of a horse shoe electro magnet made flat at the yoke and
fastened to the bottom of the box. On the top of a spindle revolving in a hole
drilled into the yoke and supported suitably is placed either a bar of soft iron or
an electro magnet or a perinanent magnet, fastened to these is a bar of copper
with tapered ends, the length of this bar corresponds to the distance between the
A spring is attached to the side
two copper pieces of the aforementioned leads.
of the box for the purpose of opening the circuit when no current is running thro
the coils of the electro magnet. A lead is brought from the storage cell on the
car to a brush or wheel which is in connection with the centre strip of the track.
this centre strip has a lead to the electro magnet, after passing thro' the coils of
the same, the circuit is continued by a lead to the return running rail which is in
connection thro' a brush or the wheel of the car with the other pole of the storage
cell. The wheels on one side of the car must be insulated from the axles.
By having another cable for the return circuit and connecting this up with the
centre strip, and by means of the brush or wheel of the storage cell aforesaid or
by a separate one, the return running rail can be dispensed with as part of the
main circuit. In this case by placing a bar of copper at right angles to the one
previously mentioned and insulated therefrom, and breaking the return circuit in
the same manner as mentioned in the case of the main, a much better insulation of
the line is secured by this double use of the magnetic switch. The method of
using this switch for series running is by providing a 3rd way to and from the
switch to the main, the revolving copper bars are at right angles to each as aforesaid
these touch No. 1 and No. 2 way when the car is on the section belonging to that
switch. The main cable is branched and brought to No. 1 and 3 way and leaves
by No. 2 and 3 way.
The circuit is as follows-In by No. 1 and then to the

page_text: motor from there to the centre strip and joins 'main thro' No. 2 way, when the
car has passed, the spring pulls the switch to No.
Dated this 15th day of March 1894.
way only.
WILLIAM ALDRED.
I, WILLIAM ALDRED of 5, Brightside Bank, Brightside, Sheffield, Engineer,
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 the propulsion of vehicles on railroads and tramways by
means of electricity.
In order that my said invention may be the better understood I have appended
the accompanying sheets of drawings in which
66
Figure 1 is a transverse section of the line, and Figure 2 plan of said line in
parallel " circuit, with single switch open on one side and closed on the other side.
Figure 3 is a plan of line in "parallel" with the double switch.
Figure 4 is a plan of line arranged in "series."
Figure 5 is a single switch in elevation.
Figure 6 is a detached plan view of a double switch.
Figure 7 is a view of the modified switch in elevation.
Figure 8 is a cross section of the track with diagram showing the flow of the
current when one rail is used as a return conductor, letter D in this figure
represents the main dynamo, E is the motor and E' is the wheel that is insulated
from the car axle.
Fig. 9 is a plan of the line when one of the rails is used as the return conductor.
With reference to the letters shown on the several figures D is the generating
dynamo E is the motor on the car H is the copper bridging bars rigidly attached
to the spindle L, J and K are two copper contacts projecting thro' the switch
box but insulated therefrom, used for making connections to the outside leads and
likewise for contact with H bridging bar. M are electro magnets in the switch
box. N is the electric cell or cells on the car. P is a graduated resistance for
equalizing the current thro' the different motors, I is an armature of soft iron
rigidly attached to spindle L and moving with it R is a spiral spring attached
either to I or H the other end being attached to the switch box side. In carrying
my invention into effect, lay down 3 lines of rails marked on drawings A, B, C,
two of these rails A and B are the ordinary rails of a tramway while C may be
any section that is most suitable. The A rail when used as a return conductor is
bonded at its junctions, at other times the bonding is not necessary. The B rail
is never bonded but allowed to remain in loose connection with its neighbour of
the same line. The C rail is shorter in length than A or B rails that are
immediately parallel with it. This to allow of sufficient longitudinal insulation
being given to the C rails between the end of one and the beginning of the next.
The lines of the drawings marked "main "return
represent and refer to
insulated electric cables that proceed from the main dynamo and which carry the
main current, they are placed below the surface of the ground.
""
"
The disposition of the 3 lines of rails A, B, C always remain the same in all
the hereinafter described modifications.
In method 1 shown in Figures 8 and 9, the current from the main dynamo flows
along the insulated main cable till it arrives opposite a closed switch, a lead which
is derived from this cable carries the current to the copper piece K this being in
contact with bridge piece H the current flows to the J piece, it (the current) is

page_text: carried from thence by a lead to the centre rail C, this being in contact with the
collecting wheel shown in the Figure 8 it flows from there to a switch under the
drivers control, from this switch it is led to the motor, then thro' the motor to a
brush that is in contact with a collecting ring on the car axle. This collecting
ring is insulated from the car axle but in electrical connection with the insulated
wheel, it flows down this wheel to the bonded rail A back to the dynamo.
The minor details of the drivers switch on the car and the brush and the
collecting ring on the axle, being so well known are not shown in the Figure 8.
In this invention the wheels upon which the car runs upon one side must be insulated
from the car axles and bearings of that side.
In method 2 shown at Figure 2 I use two electric cables to carry the main
current one cable negative the other positive, marked "main" and "return" the
current in this figure is flowing in a reverse direction to method 1.
It flows along the cable marked "main" till it arrives at the closed switch in
the manner described for method 1 from J it flows thro' the graduated resistance P
and then to rail B, the car wheel being in contact with this rail, from this wheel
to the insulated collector ring, by brush, thro' the motor, then by the drivers switch
to centre collecting wheel on C, then by a lead from C back to the dynamo by the
return cable.
In method 3 shown at Figure 3 the course of the main current is identically the
same as the foregoing with this difference, that instead of passing back direct to
the "return cable" it passes again thro' the switch box by a similar set of contact
pieces to J and K and a bridge piece H (which is insulated from the one at
right angles to it, thus causing a double make and break) and then to the return
cable.
In method 4 shown at Figure 4 which is a series method the course of the main
current is also the same but as of course in a series circuit the current must always
be "to line" I have therefore placed an intermediate pair of contacts between the
contacts at right angles to each other in the switch box.
This pair of intermediate contacts makes contact with Il bridge picce by the
action of the spiral spring R when the car has passed over the section to which
that switch belongs and thus keeping the current always "to line" either thro' the
motor and switch or thro' the switch. In all the foregoing methods the main
current working is what is referred to.
I will now proceed to describe the details of the switches. The switch consists
firstly of a horse shoe electro magnet M formed flat at the yoke to allow a
spindle L to revolve in a hole drilled in the same, said spindle being supported
on top by a bearing projecting from the side of the containing box and passing
thro' a hole in same.
Rigidly attached to this spindle by a hole drilled thro' its centre is a bar of
soft iron I which acts as an armature to the aforesaid electro magnet. Above
this bar of soft iron, is rigidly fastened a bar of copper H and in the same manner
as the soft iron bar, the length of this bar of copper exceeds the distance between
the copper contacts J and K.
The copper bar H serves the function of a bridge and the solid copper
projections J and K serve the functions of permanent connections as in an
ordinary electric switch. To the copper bar H is attached one end of a spiral
spring R the other end of the spring being attached to the side of the containing
switch box for the purpose of opening the circuit when no current is passing thro'
the coils of the electro magnet M. An explanation for which will presently be
given. The foregoing description relates to Figures 6 and 5. In Figure 7 is
shown a modification in which a bar of soft iron is pulled down by an electro
magnet M against the action of the spring R under this modification one edge of
the bar of soft iron (which would be attached to a spindle) would be placed in
close contact with one edge of the magnet M. The other edge of the bar of soft
iron is attached to a spring R the opposite end of which may be fastened to the
containing switch box.

page_text: .
A bar of copper H is rigidly fastened to the spindle L above the bar of soft
iron and at right angles thereto; the copper bar H making and breaking contact
with the permanent terminals J and K of the leads of the main current that
project into the interior of the switch box. Other modifications of the switch
arrangement might however be adopted according to the particular requirements of
each case.
Underneath the car are placed two or more collecting wheels or brushes
bearing upon the rail C; the distance between any two of these allows them to
bridge the insulated space that lies between the ends of the C rails; thus securing
continuity of contact." I will now describe the method and means by which I
work the switch as to make it independent of the main current. Upou the vehicle
I place in any suitable place a storage, or, suitable primary cell or a number of
cells; from one of the terminals of the cell I bring a lead (vide Figure 8) to a
brush that bears upon a collector ring that is in electrical connection with the
axle of the vehicle; the current flows from the axle to the wheel in contact with
rail B, a lead is brought from this rail into the switch box and there connected to
one of the terminals of the wire that is wound on the bobbins of the electro
maguet that is in the switch box (vide Figures 5 and 6) after passing around this
wire it is led outside the box and the lead is continued till it reaches the rail C,
to which it is connected. From this rail it passes to the collecting wheel (Fig. 8)
on rail C, the bearings of the collecting wheel are connected by a lead to a switch
under the drivers control on the vehicle; from this switch it is led to the other
terminal of the cell; completing the circuit. The manner in which the whole of
the arrangement works is thus As the car moves forward the collecting wheel
touches in succession different portions of the rail C, as soon as the said wheel
touches a fresh portion of C, a current from the electric cell on the vehicle flows
to the electro magnet of the switch box, the electro magnet is thus excited and
attracts the soft iron armature 1 (Figure 5) and as this is rigidly attached to the
spindle, it moves with it, carrying the copper bridge H along at the same time,
till H makes contact with J and K thus completing the circuit of the main current
to drive the motor of the vehicle; As soon as the car has passed over this
portion of the C rail, the electric cell current is thus broken; the electro magnet
of the switch box ceases its attraction of the soft iron armature, allowing the
spiral spring R to act to pull the bridge piece H off J and K, thus breaking the
main circuit thro' that switch box. The same proceeding is continued at every
switch box on the system; It will be observed that in Figures 2, 3, and 4 of the
drawings, that the electric cell N is connected up to the A rail on one side
and the Crail on the other, the reverse of the order of connecting up the same
shown at Figures 8 and 9 ; In Figures 8 and 9 the A rail is made a return
conductor and under this circumstance I connect up one of the cell leads to the rail B,
but in the methods shown in Figures 2, 3 and 4 if the connections of the cell and
motor on the car is made to coincide with the rearrangement; it is immaterial to
which of these two rails you connect the main lead; provided always that in any
modifications of the rails or connections that this rule is followed "that if the
A rail is used throughout its entire length in connection with the main current,
then the B rail is used for the connecting of the cell throughout its entire length,
or, vice versa." The direction of the cell current flowing round the cell circuit is
reversed in Figures 2, 3, and 4 when comparing them with Figure 8. 'In all other
particulars as regards the cell circuit and its working at the switch, it is the same
as previously described for Figure 8. In consequence of the magnetic switch being
entirely independent of the main current for its working; either a continuous or
alternate current can be used as a main current on this system.
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 :-
1st. On an electric tramway or railway in connection with the electric propulsion
of wheeled vehicles, the use on the vehicle of an electric cell, or a number of cells

page_text: (storage or primary) for supplying electric energy to be employed for actuating
and controlling the electro magnetic switches, which will thereby be independent of
the main current for its working substantially as herein set forth.
2nd. The arrangement substantially as herein set forth, of "leads" magnetic
switches and their connections for the purpose of supplying current to the motor
by either a "parallel " or a "series " system of conductors.
3rd. The employment of an electric cell or of electric cells on a vehicle (of a
tramway or railway) for the purpose of actuating an electric magnetic switch
placed under or near the track, said switch being employed to switch the main
current of the system, off and on automatically or under the control of the person
in charge of said vehicle substantially as herein set forth.
4th. The herein described combination system of electric railways and tramways
for the purposes herein set forth.
Dated this 14th day of December 1894
WILLIAM ALDRED.