Improvements in the Method of Supplying Electricity to Electrically Propelled Tramcars and other Vehicles, and in Apparatus therefor.
Year: 1894

page_text: Date of Application, 2nd Feb., 1894
Complete Specification Left, 3rd Dec., 1894-Accepted, 26th Jan., 1395
PROVISIONAL SPECIFICATION.
Improvements in the Method of Supplying Electricity to
Electrically Propelled Tramcars and other Vehicles, and in
Apparatus therefor.
I, PERCIVAL JOHN PRINGLE of Morningside, High View Road, Sidcup in the
County of Kent, Electrical Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to an improved method of, and apparatus for transmitting
electrical energy from a central station or other supply to an electric motor carried
by the vehicle to be propelled.
In this invention, I employ a number of short lengths of metallic conductor laid
on the surface of the road, preferably between the 2 ordinary rails on which the
car runs.
Collectors attached to the vehicle transmit electrical energy from these conductors
to the motor on vehicle & the return circuit may be completed through the wheels
and rails or otherwise back to the supply.
Sectional conductors have been used in various forms, and my improvements are
to reduce the cost of equipping a line, the number of contacts & moving parts,
so as to add to the reliability of system, the amount of electrical energy. required
to work the apparatus, and the leakage of same as much as possible.
I call each length of conductor a section, and these are kept as short as
possible so as to reduce the leakage of electrical energy from them when they are
connected with the main supply.
By preference, four collectors are used, with a space about th of the vehicle or
car length between each, the first or front collector being connected to the rails or
return through a comparatively high resistance, the other three being coupled
together, and connected to the motor through suitable switch and regulating gear.
I may also use a greater or less number than four collectors.
Whatever the number of collectors, there must be a space between the front one
& the second collector, of sufficient length, so that when the car is travelling at
its maximum speed, the time taken between the front collector and the second
making contact with a section, will allow of the distributing switch apparatus, to
be described, to fully act.
With four collectors the sections are about th of a car length, with a space
between each section equal to the distance between the centres of three collectors.
The three collectors coupled together are sufficiently wide, so that as the car
advances, the continuity of contact is always maintained between one or more of
them and the successive contacts.
The sections are grouped together into blocks, and each block is controlled
by a distributing switch placed underground or wherever convenient.
The mam insulated conductor from the supply is placed underground, and each
distributing switch controlling the different blocks is connected to it.
The sections of each block are severally connected to the distributing switch
controlling that block, and as the car advances, each section is consecutively
and automatically electrically connected to, and disconnected from the main
conductor, the disconnection from one section not occurring until the preceding
section has been put into electrical communication with the main conductor,
so that, except momentarily, one section only supplies electrical energy to the car.

page_text: The above is accomplished by means of a circular distributing switch, having a
centrally pivoted main switch arm in connection with the insulated main conductor,
working over a series of contacts.
There are the same number of contacts insulated from one another and severally
connected to the different sections, as sections in that block, and there is also one
insulated contact.
On each side of the main switch arm there is a small insulated arm which makes
connection with the contact adjacent to whichever one the main switch arm may be
in connection. Each of these arms is connected to the insulated main through
the comparatively high resistance coils of a magnet.
The action of the apparatus is as follows:-Supposing that the car is receiving
electrical energy from one or more of the collectors behind the front one, such
collector or collectors being in contact with a section which is in electrical
communication with the main insulated conductor. As the car advances, the
front collector which is connected to the rails or return through a comparatively
high resistance, is brought into contact with the next section in advance of the
car. This section being adjacent to the one which is connected to the main switch
arm supplying electrical energy to the car, it will be connected to the main
conductor through one of the high resistance magnets by one of the small
insulated arms.
This said magnet will become excited, & as the car advances, the second collector
comes into contact with this section, and short-circuits the magnet, causing the
main switch bar to be moved, and so make connection with that section in the
manner to be now described.
The two magnets are so mechanically arranged, that they act each, by the aid
of a ratchet wheel and catch, in opposing directions, one working the switch arms
clockwise, and the other counter-clockwise.
When one magnet is excited, its armature is attracted against an opposing force
such as a spring, & on its being demagnetised, the power stored up in the in the
case of the distended spring, is used to move the main switch arm and the two
small insulated arms onto an adjoining contact.
To enable a car to pass from one block to either of the adjoining blocks, each
distributing switch controlling a block, is suitably connected to the nearest section
of the blocks adjoining.
In the case of a branch line, one extra magnet would be required in the
distributing switch controlling the block before the branch line.
The blocks can be of various lengths according to the circumstances, & as not
more than one car can be in a block at the same moment, this ensures a certain
amount of safety and regularity in the traffic.
Should it be required, two or more cars can be propelled in the same block from
one distributing switch, by using one extra switch bar and actuating device for
every additional car.
For grouping together some or all of the cars when housing them at night or
for any other reason, I use a seperate switch in a convenient position worked by
hand or automatically, which actuates the main switch bar of the distributing
switch controlling the block on which the cars are to be grouped, independently of
the cars.
The distributing switch bar may be worked direct by hand without the use of a
seperate switch.
To obtain thorough lubrication of the workings parts of the distributing switch,
I propose to immerse the whole or part of it in oil. This reduces the wear and
tear, condensation of moisture, and assists in keeping the insulation good.
The cable and sockets connected to the various contact pieces of the distributing
switch may also be immersed in oil of the above mentioned reasons.
Dated this 2nd day of February 1894.
PERCIVAL JOHN PRINGLE.

page_text: Improvements in the Method of Supplying Electricity to
Electrically Propelled Tramcars and other Vehicles, and in
Apparatus therefor.
I, PERCIVAL JOHN PRINGLE, of " Morningside," High View Road, Sidcup,
in the County of Kent, Electrical 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 :-
This invention relates to an improved method of and apparatus for transmitting
from a central station or other supply, electrical energy to an electric motor carried
by the vehicle to be propelled.
In my system I employ a number of short lengths of metallic conductor which
1 call sections" laid on the surface of the road, as hereinafter explained,
preferably between the two ordinary running rails, and I use suitable collecting
brushes attached to the car for transmitting electrical energy from the said
sections to the motor on the car, and the return circuit may be completed through
the wheels and rails or otherwise back to the supply. I am aware that sectional
conductors and car collecting brushes have been used in various forms, and hence
I lay no claim to them.
The chief objects of my present improvements are to reduce the first cost of
equipping a line and the number of contacts and moving parts so as to be able to
augment the reliability of the system, and to diminish leakage of current as much
as possible and to obtain sundry other advantages. My system is adaptable to
lines on which cars run in one direction only, to single lines on which cars run in
both directions, to crossings, loops, and branch lines for same, and in fact to all
running systems and any required depôt and terminal arrangements.
In electrical traction systems of the kind above referred to it has hitherto been
usual to employ a separate magnetic device for each separate section of surface
conductor, or, to group these several magnetic devices into one box, and these
systems have been objectionable on account of the unavoidable number of working
parts and consequent cost of equipment and maintenance.
or
"
"
According to my invention I use for any number of separate surface conductors
sections" which are grouped together into one "block" one magnetic device
which I call the "distributer," and this may be placed underground or in any
convenient situation; the main insulated cable from the source of supply is also
underground and connected to each distributer of the system. Each distributer is
connected by separate conductors or "feeders to every section of a block an.
controls same, and as the car advances along the tramway each separate section
is consecutively and automatically electrically connected to and disconnected
from the main conductor, the disconnection from any one section not occurring
until the section next in advance has been placed in electrical connection with the
main conductor, so that except momentarily one section only supplies current to
the car motor at one time, and this is accomplished by the distributer above
mentioned and hereinafter fully described. The said feeders from distributers to
sections are led and electrically connected one to each section in any convenient
manner. As above stated the sections are laid intermittently between the running
rails, and each car is fitted with a proper number of collectors suitably spaced
apart. The collector which at any time is the leading collector is connected to the
rails or other return circuit through a comparatively high resistance, and acts as a
shunt collector, and the other collectors are coupled together and connected to
It is essential that
the motor on the car by suitable switch and regulating gear.

page_text: there be a space between the leading and second following collector of such
length that when the car is travelling at maximum speed the time elapsing
between the contact of the leading collector and that of the second with any one
section shall admit of the distributer hereafter described to fully act.
The coupled
collectors are made of such width as to ensure continuity of contact during
advance of the car between one or more of said collectors and the successive
sections.
My invention also comprises means for economically distributing current through
the distributer to the sections and blocks in such manner as to meet every
contingency of the working of tram lines.
"
I will describe my invention in reference to the accompanying drawings and
diagrams, explaining first the nature, construction, and operation of my distributer.
The drawings represent a distributer arranged for a single line on which the cars
run in both directions, and it is therefore capable of rotary motion and action in
both directions. This I call <6 reversing "distributer. Fig. 1 is a sectional plan,
and Fig. 2 a vertical sectional elevation with certain parts removed. Figs. 1^
and 1B are details hereinafter referred to. The distributer consists of a central
rotary arm A mounted upon a vertical spindle A' and connected to the main
insulated conductor C. The spindle A is mounted upon a bed S of slate, marble,
or other non-conducting substance as shown (which may be provided with drain
holes s. s. as shown, plugged or open, for the purpose of draining off any condensed
moisture). One end of arm A carries a laminated adjustable contact brush a
working over a series of contact pieces P1, P2, P3
124 insulated from one
another and severally connected by feeders p¹, p², p³
2 respectively to
the several sections 1ª, 2ª, 3ª . 24 of any block. Each contact piece has
a vertical rod in electrical connection, to the top of which the respective feeder is
connected as shown in Figs. 1B and 2. These rods are for the purpose of raising
the feeders above the level of the oil contained in the casing hereafter described
SO as not to injure their insulation. There is also one insulated contact P25
consisting of a strip of insulation i dividing the two contact pieces 13 and 1; this is
illustrated separately in Fig. 14, and upon this insulation i the brush a of the main
arm A rests when the distributer is not supplying current to any car. From the
top of the rods connected to these contacts 13 and 14 shunt wires are taken as
hereinafter described. Any desired number of contact pieces may be used, but in
the figure twenty-four (which I consider a convenient number) are shown and so
marked plus the above said insulated contact piece P25. The other end of the
rotary arm A carries a laminated adjustable contact brush a working over a
plate as in electrical connection with the vertical spindle A', and concentrically
arranged outside this are (in a reversing distributer) two contact rings a' a
which work respectively the inner ends of two smaller insulated arins A' A² on
each side of and connected rigidly to the main arm A and which make counection
with the contact piece adjacent to whichever one the brush a of the main arm A
may be in connection at any time. In a distributer for lines with cars running in
ope direction only, the direction of rotation of arm A would be constant and hence
only one arm A¹, one ring a', and the two shunt contacts and 12 with their
respective shunt wires are required. In the reversing distributer now under
description each of the smaller arms A1 A2 is connected through the rings a¹ a² by
leads as a to the insulated main through the coils (of a comparatively high
resistance) of the magnets M'M' respectively, the other ends of the magnet coils a
and a being electrically connected to the vertical spindle A* in connection as
explained with the main conductor C. These magnets are constructed as shown
best in the sectional view to the right of Fig. 1, and are of a known form which
give a fairly constant pull over a short distance and are therefore particularly
adapted for working this distributer. They consist preferably of a divided
core m. m', the moving part or armature m being of truncated cone shape, and the
fixed part m being formed to receive same; these cores are placed in a brass
cylinder m² upon which are wound the coils m³. The whole is surrounded by a
upon

page_text: wrought iron case m* with end pieces m³, and both magnets are fixed to a bracket m'
attached to the casing and clear of the vertical contact rods P1 P2 P3, &c. The
moving part m has a rod m³ passing through a gland or through a flexible cover or
shield such as m¹0 which serves to prevent oil entering the magnets and damping
their motion. The rods me of each magnet M₁ M² are coupled together by an
oscillating bar N mounted upon spindle A and thoroughly insulated from the
rods me by the ebonite collars m³. It is by the magnetic oscillation of the bar N
that the arm A is moved as and when required, and the required motion is derived
from the alternate actions of the two magnets M¹ M² in any convenient manner.
According to the arrangement illustrated the bar N is free to oscillate on the
vertical spindle A, and a sleeve N° is provided, and this sleeve carries the main
arm A, and at suitable level and rigidly fixed to same I mount a pair of reversed
ratchet wheels N¹ N2 each having the same number of teeth as the number
of contact points P1 P2 P³ ... . P25 in any distributer, and the edges of such
teeth coincide with one another. On the bar N and at diametrically opposite
points of the ratchets N1 N2 are mounted two pawls n¹ n2 adapted to engage the
ratchet teeth respectively. The magnet rods m³ are each connected by springs m₁l
to fixed insulated points such as m¹², from which or from any convenient part
adjacent thereto spring connections m¹³ are arranged to act on the pawls ¹, n²,
and n³ are return springs for the said pawls.
Thus the magnets through the reversed ratchets and pawls described, act in
opposing directions, one working the switch arm A clockwise and the other
counterclockwise, since when one magnet, say M¹ is excited its armature m is
attracted against the opposing force of the spring m" which is thereby extended as
also is pawl spring m¹³, thereby throwing the pawl into engagement with the
next tooth of the ratchet N' and when the same magnet is demagnetised the power
stored up in said spring m" causes the pawl n' to revolve the ratchet N' and move
same for a distance of one tooth, and at the same time the arms A A' A2 are
moved on to the next succeeding contact pieces, the acting pawl n' being then
disengaged from its ratchet by means of its return spring n³. The separately
insulated contacts respectively of contact pieces P1, P2, and 13 4 of contact
piece 25 and their respective purposes are hereinafter explained.
The whole of the above described mechanism is securely fixed in a casing or
box Q of suitable form and size with lid q. grooved for packing and all adapted to
be made oil- and water-tight.
The case is provided with suitable lugs q' for bolting down, and q² for supporting
the base plate S and with bosses and glands Q', Q² Q³-Q25 for all conductors
opposite every internal contact piece. It is constructed in the known manner and
of a form substantially such as is illustrated. This casing is filled with a suitable
oil, to about the level shown, and by this means thoroughly efficient lubrication
of all the working parts of the distributer is ensured with the object of reducing
wear and tear, and condensation of moisture is prevented and thus better insulation
is maintained.
I will now describe with the aid of Sheet 3 of the drawings attached, the working,
1st of a single line with cars running in both directions:-in which case a reversing
distributer such as is above described is required. Diagram 3; shows the arrange-
ment of connections for two reversing distributers D₁ D²-R, R¹ represent the
running rails R' being the return, the main conductor, C¹ the leads from
conductor to distributers, and D the dynamo or source of supply. 1ª, 2, 3ª, 4*,
5, 6, represent the several successive sections of one block controlled by one
distributer D', and 1, 2, 3, 4, 5, 6b, those of another block controlled by the
distributer D². For the sake of simplicity each distributer is here shown with
6 contact pieces only which are so marked; A is the main arm A' A² the smaller
arms all connected as above set forth in describing the distributer. T represents
the motor carried on the car, and 2 two collecting brushes adapted to make
rubbing contact with the several sections over which they pass and so supply the
current to the car, t is the shunt brush connected through a resistance ras above

page_text: stated to the return rail R¹. The current is supplied to the car at 4" and the shunt
brush is on 5* therefore the magnet M2 is magnetised attracting the vibratory
bar N as shown. These connections are also shown in Diagram 4.
As the car
advances in direction of the arrow the brush t² comes on section 5", as at Diagram 5,
at the same time that the shunt brush 3 is on the same section 5ª ; this short
circuits magnet M² causing bar N to be pulled back to normal position by its spring
and simultaneously causing arms A, A1, A2, to move a distance of one contact each,
as shown on Diagram 6. It will be noticed that the circuit is never broken either
on the distributer or on the sections.
The electric connections which ensue as the car passes from the block con-
trolled by distributer D' into block controlled by the distributer D2 are shown
diagramatically in Figures 7 and 8 the car being presumed to have advanced until
its brushes t¹² are receiving current from section 6* when its shunt brush will
have just made connection with section 1. A similar action occurs to that described
in reference to Figure 4, but since the magnets M' of each of the distributers D1 D2
are in parallel both will be magnetised attracting bars N of both distributers D'
and D2 and the car advances until brush 2 makes contact with section 1b which will
then short circuit magnet M¹ of both distributers D1, D2. This will cause the
bar N of distributer D to be drawn back by its spring into normal position again
moving forward the three arms A, A', A2, one contact each into the positions
shown at Figure 8. The main arm A of distributer D¹ has now advanced and lies
upon the insulated contact 7 and the current is therefore cut off from section 6ª.
The distributer D¹ is therefore in a position to feed current to a car entering on
.section 1ª or 6ª; on bar N of distributer D2 being drawn back into its normal
position by its spring it will move arms A, A¹, and A², one contact forward as also
shown in Figure 8. It will now be seen that main arm A of distributer D² is
feeding current to the car through the collecting brush t' to motor T. On the car
advancing until the shunt brush 3 is on section 2b the same action will be repeated
as has been described in reference to Figures 4, 5 and 6.
In order to reverse the car when required I provide a switch constructed as
indicated in Figures 9 and 10. The switch has 4 contacts marked f¹, ƒ², ƒ³, ƒª,
arranged to work over 3 contacts connected to the car brushes t1, t2, t3. In addition
to the resistance which has been shown up to this point as connected to the
leading brush 3 (thereby making same into a shunt brush) I employ another
similar resistance adapted to be coupled to the rear brush (thereby making it
into the shunt brush) at the same tinier is to be disconnected from brush t³ (and t²
and to become the main collectors to motor) by being connected directly to the
contacts and 13. This switch is diagrammatically shown in Figure 9, which
represents the car stopped in the same position as is shown in Figure 6.
Suppose now that a car which has been travelling in the direction of the arrow
to be at rest, as shown in Figure 9, on reversing this switch as shown in Figure 10,
and then reversing the main current to motor, brush t' would then become a shunt
brush in this case causing the magnet M' to be magnetised, and t2, 3, would
become main collecting brushes, the connections being as shown in Figure 11.
The car would then travel in the opposite direction, and a brush t2 making contact
with section 4*, as shown at Figure 12, M' would be short circuited and so actuate
the distributer in the same manner as previously described, and as will be readily
understood.
In circuit with the motor between contacts 72 and f³ and return rail R', is
arranged the usual equipment of a motor consisting of adjustable and reversing
switches and a separate main switch for breaking the main current to the car
motor, and it is necessary for this last mentioned switch to be opened before the
switch for reversing the brush connections is operated, because if the shunt
brush t³, see Figure 9, were alone in contact with the section 6ª (and so magnetising
magnet M2) the breaking of the connection of with the contact connected to
(which would be equivalent in its action to short circuiting M2) would cause the
main arm A of distributer to be moved on one contact ahead, (independently of

page_text: the car) when it might be supplying some main current, the breaking of which
would not be advisable inside the distributer.
Should the car be reversed when in the position shown at Figure 4, on breaking
the shunt resistance the magnet M2 is demagnetised, and then as above describe l
the arms A A' and A2 are moved one contact into the positions shown in Figure 13;
and the car would be supplied with current from section 5ª. As already explained
each distributer controls a certain number of sections composing a block, and the
length of the block decides the minimum distance the cars may follow one another.
Should a car gain on the preceding one, and run into its block the supply of
current would be immediately cut off same and remain so until the block was open
thus ensuring safety and regulation of the traffic. In busy parts of the line it is
evident the blocks may be composed of fewer sections.
I will now describe the means I adopt for the purpose of switching current on to
the motor of a car which has run into a block, at the time containing a car, but
the block being since cleared. This is effected by the use of a separate switch as
shown at Figure 16 and 16. It is generally required to arrange only for switching
current on to the car when it has stopped in the earlier sections of any block, say
from 1 to 4 inclusive, Figure 15. In this case I use a separate switch V adapted
to perform the same functions as the car moving over the same sections, and in the
case assumed the switch has five contacts, Nos. 1, 2, 3 and 4 being connected by
shunt wires as shown dotted to sections 1, 2, 3, and 4 respectively, and
No. which is an insulated contact. They are all arranged circularly around a
base of slate or marble, and over them a rotating arın V₁ moves, but which is not
in contact with same until it is depressed against the opposing action of a spring.
The arm V is permanently connected to the return rail R' through a resistance
This
approximately equivalent to one of the aforesaid resistances on the car.
switch is fixed in a water tight iron case placed underground and with a key
shaft coming up through same and so that the arm V₁ can be rotated over the
contact pieces; but this arm V₁ is not in contact with same until the key shaft to
which it is attached is depressed by means of a key carried by the driver; a
ratchet wheel v² is feather-keyed to shaft v and a pawl v³ is adapted to engage with
same so that it can only be turned in the direction as shown by arrow, and a key
plate is fixed on surface of road and so arranged that it is only possible to insert
and withdraw key when the said arm V' is on the insulated stop 5. In practice if
the car has stopped in position shown in Figure 15, the driver will insert his key
depressing same and slowly revolve arm V₁ making contact first with 1, and
causing a shunt current to then flow through magnet M' of main distributer D³.
On the arm V1 of switch V leaving contact No. 1 this magnet would become
demagnetised moving arms A, A', and A' of distributer D² one contact in advance
and bringing its main arm A on to contact No. 1. On arm A³ making and
breaking contact with 2 3 and 4 similar actions would successively occur and it
would then be found that the main arm of D2 had moved on to contact. No. 4 and
was therefore in a position to supply current to the car. It is necessary that
arm V of switch V should not bridge across any two contacts, and that it should
be arranged that the time taken between making and breaking contact with any
one contact, or breaking and making between any two should be sufficient to enable
the distributer to work.
In the description of my invention and in the diagrams referred to up till the
present two collecting brushes only and one shunt brush have been shown attached
to the car, but I may use a larger or any desirable number and thereby shorten the
sections and so reduce leakage of current from these when they are thrown into
connection with the main conductor, and also the number required per mile of the
line. For example in Figure 17 I show a car with five main collecting brushes (*
to to, and one shunt brush t¹.
The brushes at each end of the car are so arranged that the base of the car
beyond them will completely cover the whole length of a section before making
contact with same, so that a section which is directly connected to the main supply

page_text: -
is in no case exposed. The brushes are so spaced apart that continuity of contact
is always maintained between one or other of them and the sections as the car
advances.
:-
In the case of a one direction distributer with one shunt arm as described, if it is
desired that the section connected to the main through the shunt arm and its
respective magnet and which is always in advance of that section supplying current
to the car should always be covered by the base of the car, this can be accomplished
by bringing the sections close together and spacing the brushes on the car
accordingly. In the case of a reversing distributer with two shunt arms as already
described, the sections adjoining that section supplying current to the car are
always connected to the insulated main conductor through their respective shunt
arms and magnets, if it is desired that these sections should also be covered by the
base of the car, this can be accomplished in a similar manner by bringing the
sections closer together. Or I may to partly save this increased number of
sections (required by placing them closer together) adopt the following arrange-
ment To mechanically disconnect the shunt arm in connection with the contact
connected to the rear section, adjoining the one supplying current from its respective
magnet and so prevent this rear section being in any connection with the main
conductor, it is then only necessary to so space the sections that the one supplying
current to the car and the section in advance of same are always covered by the
base of the car both when at rest and in motion; I have illustrated one such arrange-
ment in Figures 19 to 21; where Y is a T shaped arm pivotted at y with two of
its arms y and y² insulated from one another and electrically connected respectively
with the shunt arms A1, A2, of distributer, this rocking arm Y is pivotted upon the
distributer arm A but insulated therefrom. When therefore the arm A is on the
insulated contact 7 these arm pieces y', y' of the rocking arm Y will be in contact
respectively with the contacts 1, 2 connected to magnets M³ and M² as shown.
On the distributer arms moving counterclockwise a spring catch such as a pivotted
to some fixed part is arranged to engage the arm piece 3 and tilt over the arm Y
into the position shown at Figure 20, and so disconnect the rear shunt brush from its
respective magnet. On the arm Y tilted as in Figure 20 being rotated by the
distributer arms the arm piece y³ meets the pivotted spring catch piece ² tilts and
passes same and is then sprung into its normal position by the stop when
distributer is not in use, as shown in Figure 19. If the distributers arms had
been moved in the reverse direction the rocking arm Y would have assumed
the position shown at Figure 21, disconnecting the then rear brush from its
respective magnet.
It will be seen that in this case and every case so far described, that the first
and last sections of a block when a distributer is not in use are both connected
to the main conductor through the shunt arms and magnets of distributer.
I show in Figure 22 how the 1st contact of D2 which is connected to the first
section 1 of a block, may be connected to contact 7 of D₁ so that when D2 is not
in use its shunt arm A has no connection with its respective magnet even when
the main arm A of D' has been advanced onto contact 6. For this reason I have
added to each arm A¹ A2 an additional shunt contact arm A" and A2 fixed side
by side but insulated therefrom. I have divided the contact into two parts 1³
and and added the additional contact on No. 1 and the shunt wire connecting
it to 13. Thus when arm A comes onto contact 6, A" connects 13 and so puts the
shunt arm A¹ of D2 in connection with contact 1 of D2 and when this occurs (with
sections arranged for the one direction distributer as above described and with the
device described in reference Figures 19. 20 and 21,) at no time are the main
supply sections or any sections which are connected to the main conductor through
the comparatively high resistance magnets, exposed beyond the ends of the cars.
When distributer D is not in use there would be similar contacts and connections
between contact 6 of D¹ and contact 7 of D².
The arrangement for a branch from a single line adapted for cars running in
both directions is shown at Fig. 14, where distributer D₁ controls the sections 1"

page_text: to 6, and the two distributers D* and D³ control the sections 1 to 6 and 1º to 6°
respectively of the branch lines. D' and D³ distributers and their connections are
similar to those shown in Fig. 3, but D' distributer-which controls the block
before the points to the branch-has an additional shunt arm A³ adjoining the
shunt arm A, and the contact piece P (referred to in Figs. 1 and 14) instead of
being in one piece (13 above specified) is divided into two as shown at 3 and 1,
each part being insulated from the other. When the main arm A is in the position
shown in Fig. 14 the two shunt arms A3 and A³ make contact respectively with
contacts and 14, and again are respectively connected by shunt wires w³ to to
contact of distributer D2 and of distributer D³. The shunt arms A and A³
of distributer D' are connected to main insulated conductor C through the two
magnets M2 and M³ respectively. The two moving armatures of these magnets are
coupled together so that either of them being magnetised would pull down the
rocking bar N. In practice this would be more conveniently accomplished by
having one magnet with two independent windings. My reason for requiring
these two magnets or one magnet with separate windings is hereinafter described.
Now suppose a car is in position, as shown in Fig. 14, with shunt brush * on
section 1, and the motor receiving current by brushes 2 and t¹ from section 6ª, it
will be found that magnet M³ of distributer D' and M2 of distributer D' will
become magnetised. As the car advances t' makes contact with section 1 and
short circuits these magnets, moving the contacts A. A' A' and A3 of distributer D'
forward for one contact in advance, thereby bringing the main arm A onto the
insulated contact 7 and moving the arms A. A' and A' of distributer D' forward
one contact so as to bring its main arm A in connection with contact piece 1 and so
supply current to section 1°. Taking the case of the car running into section 1° of
the other branch, similar connections would be made between distributers D' and D³,
but magnet M2 would be actuated instead of M³.
I will now describe the reason why distributer D' requires two magnets M³ and M*
or one magnet with two separate windings. This is because if the two shunt
wires wow running from contacts of D³ and 1 of D³ were taken to one contact
and from thence through one magnet M² to C instead of two separate contacts 13
and, and two magnets, on the car being iu the position as shown with the shunt
brush on section 1, it would be found that magnet M³ of distributer D¹ and
magnets M of D2 and D³ would all become magnetised, but by separating these
contacts am able to obtain independent working between distributers D' and D³.
With cars travelling in the opposite direction on either of the branches, when
the leading or shunt brush of car makes contact with section 6ª, distributer D'
having its main arm on contact 7 would cause (on whichever branch the car was)
through the agency of shunt arm A' (which would be on contact 6) the magnet M¹
to become magnetised, and at the same time magnet M' of distributer D (or D³
according to which branch car was on) to also become magnetised. As the car
advances the magnets would be short circuited and the distributers actuated as
previously described, when D' would then supply current to the car, and either D'
or D (according to which had been supplying current to car) would have its main
arm A moved on to insulated contact 7.
It will be seen therefore that the objects of the small contacts 1 and 1 of
contact pieces 1 and 6 are the following. Should a car advance so that shunt
brush comes on section 1° when a car is already in the block controlled by
distributer D³, the shunt arm A' of D³ not being in the position shown as connecting
across and contact 1, would not permit of magnets M² of distributers D' and D³
being magnetised, so that on the car advancing until its rear brush t' left section 6ª,
the main current supplying the motor would be broken at the section 6* instead of
inside distributer D where it might damage the contacts.
I will now describe one method of grouping the cars close together as is required
at the depôts, termini, or at busy junctions or other places.
Referring to Fig. 18, D2 is a distributer controlling six sections 1 to 6', 6' being
12

page_text: the terminus of a line. In practice for depôt or terminus arrangements it would
only be necessary to group the cars on a small number of sections of the block.
From each of such sections a shunt wire is taken to contacts 1, 2, 3, 4, 5, and 6 of
the separate switch W which would be placed in some convenient position near
where this grouping is required. A shunt wire is also taken from contact 7 of
distributer D to contact 7 on switch W, and there would also be an insulated off
contact 8. Over these circularly arranged contacts the arm w rotates, but this arm
does not make connection with any contact until depressed, and is connected to the
return R¹ through a shunt resistance 3 (about equal to the shunt resistance on
the car).
Now assuming that a car has entered the block controlled by D2 and run to
the terminal section 6° in the position as shown leaving the main arm A of D² on
contact 6. Before another car can enter this block it is necessary that the main
arm A should be moved on to the insulated contact 7, and this is done by means of
the switch W in this mauner. The normal position of the arm w would be on the
insulated contact 8, and the driver of the car would revolve this arm (at the same
time depressing same) over the contacts in the same direction as the car has
travelled over the sections, that would be clockwise as drawn.
On this arm w
making connection with contacts 1, 2, 3, and nothing would happen, as the
arms A, A', and A2 of distributer are not connected to these, but on it making
connection with contact 5 it would cause magnet M' of distributer D to become
magnetised, and on it breaking connection with contact 5 M' would become
demagnetised moving the arms A. A¹ and A2 so that arm A comes on contact 6
of distributer D², Then on arm to making connection with contact 6 of W,
M² then becomes magnetised because arm A² is in connection with contact 6 of
distributer D². On arm w breaking connection with contact 6 of W, M² becomes
demagnetised moving arms A, A', and A² on one contact so that A2 again now
comes on contact 7. Should however the car collecting brushes t¹ and t² be just
in connection with section 5 and 6 this action just described would not occur,
as magnet M would not become magnetised with the contacts 5 of D2 in con-
nection with contact 6 of D2 which is directly connected to the main insulated
conductor through the main distributer arm A. In the same manner by arın w
making and breaking connection with contact 7 of W the arms A. A' and A' of
distributer D² are moved so that its main arm A is on insulated contact 7.
the next car running on to section 5ª or 4", whichever the case may be, the arm w
would again be depressed and rotated by the driver or attendant with the same
actions taking place as afore described, but these actions commencing with
contacts 3 or 4 (according to which section the second car has stopped on) of W
instead of with contact 5, and so on in like manner for every car.
Suppose the
last car is on section 3* and it is required to start the cars out of the terminus or
.depôt. The main arm A of D2 would have been returned to the insulated contact 7
by means of the switch arm w of W having been revolved in connection with the
contacts above described after this last car had entered the depôt or terminus.
Now to start this last car it would be necessary for the driver or attendant to
depress and revolve the arm w of W over the contacts in the same direction as
before, that is, clockwise, stopping and releasing same on whichever contact is
connected to the section on which the main brushes of the last car are, in this case
contact 3, and then returning it to the insulated contact 7. This making and
breaking contact with the successive contacts would actuate the distributer arms A.
.A' and A² step by step until the arm A2 was on contact 3 of D2, and, M² being
magnetised, the releasing of arm w of W would cause the arms A. A A² to move
one contact, bringing the main arm A onto section 3 ready to supply current to
the car.
On this car leaving the depôt or terminus and proceeding into the next
block the main arm A would be returned to the insulated contact 7 of D2, and, on
the switch W being operated in a similar manner to that just described, the arm A
would again be moved into the contact in connection with the section on which
On

page_text: are the main brushes of the last but one car, and would be ready to supply current
to same. Each car in succession on leaving the depôt or terminus would require
similar operations.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a system of electric traction such as is above referred to (having a number
of short conducting sections forming each block) the use and adaptation of a single
current distributing apparatus arranged or operating substantially as above set
forth for controlling successively every section of each separate block and having
(a) for tram lines on which cars travel constantly in one direction one
magnetic device consisting of one magnet M¹ and electrical connections
adapted to automatically actuate a main current distributing arm A with
one shunt arm A' arranged to rotate over contact pieces in one direction
only, the circuit connections being made substantially as set forth, and
(b) for lines on which cars travel in both directions a reversing magnetic
device comprising two magnets M' M² and electrical connections adapted to
automatically actuate a main current distributing arm A with two shunt
arms A' A² arranged to rotate in both directions over contact pieces, the
said magnetic device being adapted for successively connecting the main
current from the source of supply to the said separate sections and discon-
necting same as and when required, and the circuit connections being made
and the whole being arranged or operating substantially in the manner
specified.
2. The combination and arrangement of parts comprising the reversing distributer
for lines with cars running in both directions, comprising essentially the rotary
current distributing arm A, the shunt brush arms A1 A2 operated substantially as
above shown, the magnets M' M², rocking bar N, and ratchets or equivalent means
of transmitting the required step by step rotary motion, the contact pieces, feeders,
and connections all being arranged or operating substantially in the manner and
for the respective purposes above set forth.
3. The modification of the arrangement of distributer last above referred to for
lines with cars constantly running in one direction comprising the combination of
the rotary current distributing arm A, one shunt brush arm A, one magnet M',
the bar N, and ratchets or equivalent means of transmitting its motion to
arms A. A', the contact pieces, feeders, and connections being arranged and
adapted to operate substantially as and for the purposes above set forth.
4. In effecting the electric propulsion of cars by the means above indicated
the employment of a shunt brush on the car directly in advance of the main
collecting brushes, and adapted to act in conjunction with the magnetic devices of
each distributer in such manner as to actuate the same by a shunt current directly
across the mains, substantially as above set forth.
5. In a system of electric traction and distribution such as is above referred to,
(a) The arrangement of a supplementary reversing switch adapted to operate
substantially in the manner and for the purpose set forth in reference to
Figs. 9 and 10.
(b) The arrangement of apparatus and electrical connections for working a
branch from a single line on which cars run in both directions as described
in reference to Fig. 14.
(c) The arrangement for supply ing current to the motor of any car which has
run onto any section of a block then occupied but just cleared, consisting of
a separate switch constructed or adapted to be operated substantially as
described in reference to Figs. 15, 16, 16, and 18, by a separate key for
independently actuating the distributer connected to such sections so that
it supplies current to the car motor.

page_text: (d) The provision and arrangement in combination with a reversing distributer
of apparatus such as is described in reference to Figs. 19 and 20 and 21 for
electrically disconnecting the exposed section immediately in the rear of
the section supplying current to an advancing car substantially as set forth.
(e) The hereinbefore described means of and apparatus for electrically discon-
necting one or both of the terminal sections of any block from the main
supply until covered by a car as and for the purpose above set forth in
reference to Fig. 22.
6. The arrangements of apparatus and connections for grouping cars together at
termini, depôts, and such like places, substantially as set forth in reference to
Fig. 18.
7. The hereinabove described improved means of effecting the electric propulsion
of tramcars which consists in transmitting current from a central supply through a
distributer or a series of distributers such as are described to the several and
successive sections of each block and the successive blocks of the tram line, and
disconnecting same, and generally working the line as may be required, all
substantially as above set forth.