Improvements in Staff Apparatus for Controlling the Traffic on Single Line Railways.
Year: 1890

page_text: Date of Application, 12th June, 1890
Complete Specification Left, 2nd Mar., 1891-Accepted, 4th Apr.,
1891
PROVISIONAL SPECIFICATION.
Improvements in Staff Apparatus for Controlling the Traffic on
Single Line Railways.
I, ARTHUR MOORE THOMPSON, of Crewe Works, Crewe, in the County of
Chester, Mechanical Engineer, do hereby declare the nature of this invention to be
as follows:-
:-
Letters Patent were granted to Francis William Webb and Arthur Moore
Thompson dated the 23rd day of January 1889, and numbered 1263 for "Improve-
ments in staff apparatus for controlling the traffic on single line railways" and I
now describe how I propose to improve this our said apparatus by electrically
controlling it by one line wire instead of two line wires.
To accomplish my object I employ an electro-magnet with a closed magnetic
circuit, which may be described as a ring magnet or as being of the form of two
ordinary electro-magnets placed together pole to pole the metallic continuity of
the cores being unbroken except where they form the usual junction with the
breech pieces.
The coils of one half of this magnet are traversed by a current from a local
battery which current always flows in one direction say from the copper pole of the
battery and I term these coils the local coils.
The coils of the other half are traversed by the current sent from the distant
station and this current is reversed in direction and polarity by a suitable
commutator so that the flow in one position of the commutator is from the copper
pole of the distant station battery and its direction through the coils non opposed
to the current flowing through the local coils, or it is from the zinc pole of the
distant station battery and its direction through the coils opposed to the current
flowing through the local coils, the flow in the other position of the commutator
is from the zinc pole of the distant station battery and its direction through the
coils non opposed to the current flowing through the local coils or it is from the
copper pole of the distant station battery and its direction opposed to the current
flowing through the local coils. I term these coils the line coils.
Now referring to our Patent of the 23rd January above mentioned I will assume
that the apparatus there described is provided with the electro-magnet now described
together with a suitable commutator that the staffs in each apparatus are all in,
that the section of railway worked is clear and that each apparatus has its commu-
tator so turned that a current sent from either would be from the copper pole of
its battery and its flow in direction through the line coils non-opposed to the current
traversing the local coils.
Station A. rings to station B that he has a train waiting. Baccordingly sends a
current from the copper pole of his battery through the line coils of A's apparatus,
the local coils of A's apparatus are also traversed by a current from the copper
pole of the local battery and the two currents being non-opposed, a powerful
magnetic attraction is generated at the pole pieces which are placed between the
line and local coils, and in consequence the lock armature is attracted enabling A
to withdraw a staff.
The withdrawal of the staff reverses the commutator of A's apparatus switching
the line wire from the copper to the zinc pole of A's battery and at the same time
switching the line wire from one end to the other end of the line coils in A's
apparatus. The result of this is that if B now sends another current from the
copper pole of his battery it traverses A's line coils in a contrary direction and
opposed to the current traversing the local coils and consequently the one current

page_text: being opposed to the other no magnetism is induced at the pole pieces and A's
apparatus remains locked.
If A. now sends a current to B from the now zinc pole of his battery it traverses
B's line coils in a direction opposed to the current flowing through B's local
coils as B's apparatus is still switched on to the copper pole of his battery and
the line so switched to the line coils that only a current sent from the copper pole
of A's battery would traverse the line coils in a direction non-opposed to the
current traversing the local coils. Consequently B's apparatus remains locked.
A can now replace the staff withdrawn from his apparatus and restore the
working as it was before, or the staff withdrawn may be taken to B and placed
in B's apparatus. This action would reverse the commutator of B's apparatus
switching the line wire from the copper to the zinc pole of B's battery and at the
same time switching the line wire from one end to the other end of the line coils.
This places B's apparatus again in unison with A's as each apparatus is sending a
current from the zinc poles of their batteries and the direction of this current is so
switched that it traverses the line coils of each apparatus in a direction non-opposed
to the currents traversing the local coils consequently A can unlock B's apparatus
or B can unlock A's.
The withdrawal of a staff from either apparatus places them in disunion again
and both remain locked until the staff withdrawn is replaced in one apparatus or
the other when union is again established.
Dated this 11th day of June 1890
A. MOORE THOMPSON..
COMPLETE SPECIFICATION.
Improvements in Staff Apparatus for Controlling the Traffic on
Single Line Railways.
I, ARTHUR MOORE THOMPSON, of Crewe, in the County of Chester,
Mechanical 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 :-
Letters Patent were granted to Francis William Webb and Arthur Moore
Thompson dated the 23rd day of January 1889 and numbered 1263 for " Improve-
ments in staff apparatus for controlling the traffic on single line railways" and I
now describe how I propose to improve this our said apparatus by electrically
controlling it by one wire instead of two.
To accomplish my object I employ an electro-magnet with a closed magnetic
circuit which may be described as a ring magnet being of the form of two ordinary
horse-shoe electro-magnets placed together pole to pole the metallic continuity of
the cores being unbroken except where they form the usual junction with the
breech pieces. The coils of one half of this magnet are traversed by a current from
a local battery which current always flows in one direction say from the positive
pole and term these coils the local coils. The coils of the other half are traversed
by a current sent from a distant station and this current is reversed in direction
and polarity by a suitable commutator so that the flow of the current in one position
of the commutator will act in conjunction with the flow of the current through the
local coils and thus combine to energise the poles of the magnet or in another
position the flow will be opposed and thus no magnetism will be induced.
In order that my invention may be more clearly understood I will now describe
it by the aid of the accompanying drawing.
Figure 1 is a sectional elevation of the magnet the section being taken through
the centre of one of the cores.
Figure 2 is a side elevation, Figure 3 plan, Figure 4 is a diagram showing the
magnet, commutator switches and leads for one instrument.
A Figures 1, 3, 4, shows the local coils, B Figures 1,3,4 the line coils, C Figures 1,3,4

page_text: the magnet poles. The magnet is carried on an arm D turning on a centre E and
this arm together with the magnet is mechanically lifted by the tail piece F, this
lifting being done by a projection on the staff when it is being withdrawn.
G Figures and 4 is an armature which is normally in contact with the poles CC
of the magnet and it is lifted with the magnet when the staff is withdrawn when
the magnet is energised. Referring to the diagram Figure 4, this represents the
instrument say at station Y, and at station Z at the end of the line wire is a
similar instrument. All staffs being in the apparatus the switches of both instru-
ments are as shown by the diagram. I will now work a train from Z to Y so as
to clearly explain the action of the magnet. Station Y having obtained permission
to take a staff he first of all reverses the position of switches a and a this passes a
current from the local battery through the switch a to the local coils of the
magnet A.
then sends a current from the negative pole of his battery by
reversing the switch which enters Y instrument at passes through to "",
to to g, to h, to i, to j, the switch à' having been reversed with the switch a the
current passes through k to the magnet B flowing through the coil so as to act in
conjunction with the current flowing through A. the magnet being thus energised.
The current then passes to 1, to m, to n and completes the circuit through earth.
Y now withdraws a staff and the withdrawal of the staff reverses the position of the
switches in Y's instrument marked m, n, d, c. If Z now sends another current
which would be of the same polarity as that previously sent it would enter Y's
instrument at and its direction reversed through o to to the magnet B, passing
through the coils in the reverse direction and consequently opposed to the current
flowing through A no magnetism being thus induced.
f
If the staff withdrawn from Y is replaced in Y's apparatus the working is restored
as before, but if it is carried to Z and placed in Z's apparatus then the act of
putting the staff in reverses the switches m, n and d, in the same way as they
were reversed by the withdrawal of the staff in Y's apparatus. It will be seen that
the reversal of these switches not only reverses the direction of the current through
the coil of the receiving instrument but it reverses the polarity of the current sent
from the distant station and it will thus be seen that the negative current previously
sent by Z is now changed to a positive current and this current being now sent from Z
to Y would energise the magnet of Y's apparatus in the same way as the negative
current previously energised it because although it is of an opposite polarity its
direction in Y's apparatus has been reversed consequently the positive current now
acts on the coils in the same way as the negative current previously acted before
the switches m, n, d, e, were reversed.
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:
An electro-magnet with a closed magnetic circuit energised by two separate and
independent currents in connection with apparatus for controlling the issue of staff's
or their equivalents for the working of single line railways substantially as
described and illustrated.
Dated this 28th day of February 1891.
A. MOORE THOMPSON.