Improvements in or Connected with Electric Rail or Tramway Systems.
Year: 1888

page_text: Date of Application, 18th Aug., 1888
Complete Specification Left, 15th May, 1889-Accepted, 3rd Aug., 1889
PROVISIONAL SPECL ATION.
Improvements in or Connected with Electric Rail or Tramway
Systems.
I MICHAEL HOLROYD SMITH of Royal Insurance Buildings Halifax in the. County of
York Engineer do hereby declare the nature of this invention to be as follows:-
--
In specification No. 5627 of 1885 and Provisional Specification No. 5198 of 1888 1
have described certain improvements in electric rail or tramway systems and my
present invention is particulary applicable for use with such systems, although it may
be used in connection with other forms and constructions, several of which have been
previously patented by me.
According to this invention I propose to use a main supply cable from: which the
current is led to insulated motor bar sections through suitable switches; for operating
which a separate and distinct sectional conductor is employed... The return current.
from the car passes by means of the rails or by a second conductor as may be
preferable.
The nature of the invention may be more fully set forth by describing the manner
in which the car is operated. Let it be assumed that said car is at the terminus and.
the motor and switch contact makers are both on their respective first sections.-The
switches on the car being brought into position, the current from the main cable
passes through the switch section and automatically (by the action of magnets) con-
nects the motor bar section with the main cable when the car will at once move'and
traversing section "one come to section "two," when the last contact piece of switch
will be drawn over, breaking the circuit to the motor bars of section "one," the action.
of the magnets and contact piece of the switch being such that the circuit to the motor
bars cannot be completed without at least a clear section be left. between two cars on
the same line.
"
If preferred the switch section may be operated by a battery carried by the car, the
action of the magnets and contact piece being as described.
In order to avoid a flash, should the motor contact maker run onto a blocked section,
the ends of each section have resistances introduced and both the motor bars; and
switch sections are made to overlap or break joint so that before the contact makers:
leave one section they switch on the next (if unblocked) thus preventing even a
momentary break in the supply of electricity to the train.
It must be understood that separate conductors are used for operating the switches
and for conveying the current to the motor on the car, and that a separate: switch is
provided for each section (although I may arrange for one switch to control two
sections) and that the switch conductor operates and controls two sections; making
and maintaining contact between the insulated conductor and motor bars. on the
section where the train is, and breaking and holding off the current from the section
immediately behind, and that the main current does not. pass through; the switch
bars.
11
101 1
C
1000
COMPLETE SPECIFICATION.
Improvements in or Connected with Electric Rail or Tramway
Systems.
I MICHAEL HOLROYD SMITH of Royal Insurance Buildings Crossley Street Halifax
in the County of York Engineer do hereby declare the nature of this invention and in
Price 8d

page_text: what manner the same is to be performed, to be particularly described and ascertamed
in and by the following statement :-
In specification No. 5627 of 1885 and Provisional specification No. 5196 of 1888 1
have described certain improvements in Electric rail or tramway systems and my
present invention is particularly applicable for use with such systems, although it may
be used in connection with other forms and constructions several of which have been
previously patented by me.
According to this my invention I propose to use a main supply cable from which
the current is led to insulated motor bar sections through suitable switches for
operating which a separate and distinct sectional conductor is employed. The return
current from the car passes by means of the rails or by a second conductor as may be
preferable.
The nature of the invention may be more fully set forth by reference to the
accompanying drawings.
Fig. 1 is a diagram illustrative of my invention.
Fig. 2 is a side elevation of a switch to be used therewith.
Fig. 3 is an end sectional elevation of fig. 2 on line A-B.
Referring to to diagram Fig. 1 the "main cable" is an insulated conductor placed
in any suitable position preferably on or under the ground, or in an underground line
at the side of the tunnel. "Earth rail" is one of the ordinary rails upon which the
coaches run, these when used as the return conductor would be electrically connected
with each other and the negative terminal of the dynamo or generator, the positive
terminal being connected to the "main cable."
The "motor bars" shown in three sections A. B & C would in practice be preferably
similar to those described in patent No. 5196 of 1888-though other forms could be
used with efficiency.
The "switch wires are preferably wires suspended above the train but may be strips
of metal under the carriages or rods at the side as may be most convenient. 5 repre-
sents the coach or train containing a motor 6 and switches 7 & 8. 71 and 8¹ are
sliders or gatherers 7¹ making contact with the "switch wires" and 81 with the motor
bars. No. 1 No. 2 No. 3 are controlling switches.
The operation is as follows. The coach or car 5 is supposed to be moving in the
direction indicated by the arrow, it has left section A and is upon section B the switch
contact maker 71 sliding upon the "switch wire" of section B permits a current to
pass round magnet 6 of switch No. 3 energizing it and drawing over the lever 9 so as
to connect the wires leading from the main cable" to the "motor bars" of section B.
The slider 81 by its wires passing the current through switch 8 to the motor 6 and
through the wheels to the rails forming the return earth. The slider 7' also permits a
current to pass round the magnet 6 of switch No. 2 holding the switch lever 10 against
it, therefore should a following train reach section A whilst the present one is on
section B although its switch slider allows a current to pass round magnet a of
switch No. 2 it cannot draw over the switch it being held by magnet b, and there
being no connection between the main cable and terminal 11. no current is available
in the "motor bars" of section A. and the train must therefore stop until the pre-
ceding train has left section B when magnet b of switch No. 2 ceasing to be
energized magnet a will draw the lever 10 on to terminal 11.
"
Whilst the "following train was stopped on section A a current would be passing
through magnet a of switch No. 1 and blocking the preceding section.
In order to avoid a flash when the motor slider runs off a live section on to a
blocked section the ends of each section may have resistances introduced as shown
by r: r. r.
"
The "motor bars" and "switch wires
are made to overlap or break joint so that
before the sliders leave one section they switch on the next, (assuming it is not blocked).
There is therefore no break in the supply of electricity to the train. The normal
position of the switches is as shown in No. 1 & 2 thus minimumising the loss of power
through leakage as no current passes to the exposed motor bars unless required by a
train. If this economy of power is not desired it is obvious that double terminals and

page_text: connections may be used one for each magnet of the switches this would not prejudice
the blocking but would give a double course for the current from the "main cable"
to the operating "motor bars."
Instead of the magnets being operated by a current from the "main cable " they
may be energized by a current from a battery carried by the train in manner similar
to that described by me in patent No. 17018 of 1886.
It is obvious that the "switch wires" and magnets may be used for signalling purposes
instead of automatically blocking as herein described. The magnetic switches being
used to operate a semaphore or other signalling device instead of breaking the main
circuit.
For carrying out the herein described system of signalling and blocking trains
various devices of switches and contact makers or sliders may be employed.
Figs. 2 & 3 illustrate a switch specially suitable for this purpose.
24 & 25 are magnets their poles are marked N-S. 26 & 27 are armatures free
to turn or rock between the poles, these armatures are keyed upon a spindle 27'
which carries the insulated lever 28 the magnets are fixed upon a curved bed and can
be turned to any angle with each other they are preferably placed as shown viz. at
an angle of 60° (line C-D.).
Supposing magnet 21 to be energized then its armature turning, brings the
lever 28 into contact with the clip 29 and the current can pass from the supply by
the wire 30 to the "motor bars" by the wire 31.
If the current ceases to pass round magnet 24 and is allowed to pass round
magnet 25 its armature turns the lever 28 into clip 32 making connection with
another section.
The method of maintaining contact with the moveable lever 28 will be sufficiently
apparent from the drawings."
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
1st. In electric or other railways or tramways the employment of separate
sectional conductors having communication with the train for blocking or signalling
substantially as herein illustrated and described.
2nd. In electric railways or tramways the employment of a separate wire or other
conductor distinct from the main circuit for signalling or controlling purposes,
substantially as described.
3rd. In electric rail or tramway systems the combination of an exposed conductor
making contact with the moving train, electric battery and switches for signalling
purposes substantially as herein set forth.
4th. In electric rail or tramways the employment of sectional conductors that
break joint or overlap each other.
5th. The combination of sectional conductors overlapping joints and interposed
resistances substantially as and for the purpose described.
6th. The combination of "main cable" "switch wires" "motor bars" and switches
substantially as and for the purpose herein illustrated and described.
7th. Electric switches as illustrated by Figs. 2 & 3 substantially as and for the
purpose described.
Dated this 14th day of May 1889
M. HOLROYD SMITH.