Improvements in Electric Indicators.
Year: 1887

page_text: Date of Application, 28th Oct., 1887
Complete Specification Left, 26th July, 1888
Complete Specification Accepted, 31st Aug., 1888
Improvements in Electric Indicators.
1 GEORGE EDWIN FLETCHER of 93 Chatham Street Edgeley Stockport in the
County of Chester, Telegraph Engineer and Electrician do hereby declare the nature
of this invention, to be as follows:-
The object of this Invention is to improve and cheapen the method of producing
Electric Indicators for Railway Telegraphs, Block, Speaking, Indicating or Telephone
circuits, by means of needles, flags or discs, and for this purpose I employ a compound
needle which may be either an Electro, Permanent, or Induced magnet, carrying
a Pointer, Flag, or Disc or not, as required for indicating purposes.
The form I preferably give to this compound needle is substantially as follows:--it
is of horse-shoe shape with a piece of Iron wire, Block of Iron or steel placed
tangentially to it, and at right angles to its axis on which it rocks, and which may bo
either horizontal or vertical. This needle is kept in its normal position by magnets
which may be either electro or permanent magnets. It is obvious that these magnets
become the inducing magnets.
The ends of the horse-shoe shaped needle dip into two hollow bobbins or coils,
which are wound with insulated wire, and have their axes vertical or horizontal as the
case may be, but in all cases at right angles to the axis of the compound needle.
When a current is sent in one direction through the coils one end of the needle
is drawn into one of the coils and the other end is repelled by the other coil. With a
reverse current the effect is opposite by this means producing the necessary movements
of the Indicating needle, Flag or Disc.
3711
Lobo 1007

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Indicators.
I, GEORGE EDWIN FLETCHER of 93 Chatham Street, Edgeley, Stockport, in the
county of Chester, Telegraph 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:-
The object of this invention is to improve and cheapen the method of producing
Electric Indicators for Railway Telegraphs, Block, speaking, Indicating, or telephone
circuits, by means of needles, flags, or discs--and for this purpose, I employ
a compound needle, which may be either an electro, permanent or reduced magnet
carrying a pointer, disc, or flag, or not as required, for indicating purposes.
:-
The form I preferably give to this compound needle is substantially as follows:-
It is of horse-shoe shape and of iron, with a piece of iron or steel placed tangentially
to it, and at right angles to the axle upon which it rocks. The axle may be either
horizontal or vertical. The needle is kept in its normal position by means of magnets,
which may be either electro, or permanent magnets. It is obvious that these magnets
become the inducing magnets. The ends of the points of the compound needle dip
into two hollow bobbins or coils, wound with insulated wire, having their axes either
vertical or horizontal as the case may be, but in all cases at right angles to the axis of
the needle.
When a current is sent through the coils in one direction, one end of the needle.
is drawn into one of the coils or bobbins, and the other end is repelled, or driven out
of the other coil or bobbin with a reverse current the effect is opposite, thus producing.
the necessary movements of the indicating needle, flag, or disc.
The Figures on the accompanying sheet of Drawings shew one construction of
apparatus according to my Invention.
Fig. 1.is a front view of the compound needle.
Fig. 2 shews the arrangement as a whole and is a front elevation.
Fig. 3 is the plan of Fig. 2.
In Fig. 1. "a" is the axle, "6" a small block by means of which the needle
is attached to the axle, "c" is the needle, and "d" a small piece of iron or steel
attached to the same. The whole will be seen in position in Figs. 2 & 3-
marked "e."
e
دوم
In Figs. 2 & 3.“
"is the compound needle, which is induced by the magnets ",,"
the poles of which are indicated by the symbols "N. N-S.S," the coils or bobbins
wound with insulated wire are marked "g" & "g""-("g" being shewn in section in
Fig. 2.) “h” is a small table or platform supporting the coils "g, g¹"—“g” is a
small cock carrying the centre for the axle of the needle, and "k" a bridge serving
the same purpose, "1,1" are clips by means of which the magnets "f, f" are held in

page_text: position: "p" is an indicating needle which may be either a disc or flag as required,
q" is the foundation carrying all the other work.
It will be seen in the magnets "ff," that the poles "S, S" induce in the points of
the needle "m, m',"-"North "-seeking poles, and at the same time those marked
"N,N" produce "South "-seeking poles about the place marked "n."
The small piece (marked "d" in Fig. 1.) has "South" seeking poles also induced
in points marked "o, o"--and it follows that when a curront passes through the coils
marked "
9, g" in a certain direction that the point "m" is drawn into the coil " 'g"
and at the same time, the point "m¹" driven out of the coil "g" -with an opposito
current the reverse action will take place.
0,
The point "m" having come nearer to the point "N" in the case described, would
have a tendency to cause the needle to remain in the position in which the current
had placed it, and for that reason the piece o" is employed, the magnets heing so
arranged that the distance between the points "o " and "N" or the points "o" and
"N" is always less than the distance between "N" and any part of the needle
between m and "m¹."
35
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare what I
claim, to be
First. The form of needle substantially as described in the above.
Second. The manner of inducing the needle, and of bringing the needle to its
normal or vertical position substantially as herein-before described.
Third. The combination of the whole as substantially described in the foregoing
specification.
Dated this Twenty fifth day of July 1888.