Improvements in Electrical Signalling Apparatus for Police Service and the like.
Year: 1890

page_text: Date of Application, 10th Sept., 1890-Accepted, 8th Nov., 1890
COMPLETE SPECIFICATION.
Improvements in Electrical Signalling Apparatus for Police Service
and the like.
I, ROBERT DUNBAR RADCLIFFE, of 50 Lime Street, in the City of London'
Attorney and Electrician, 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 electrical signalling apparatus for police service and
the like, and more especially to apparatus of the kind or class described in the
Specification of former Letters Patent granted to me and dated April 22nd A.D. 1890
No. 6126.
An important feature of my presont invention consists in arranging the insulating
pieces, recesses or spaces in the signal disc or wheel in such a manner that, when the
latter is rotated under the action of clockwork or otherwise the brush or contact arm
will be moved into the path of isolated insulating picces recesses or spaces arranged
in groups in different concentric circles instead of into the path of insulating pieces
or recesses arranged in different radial lines as heretofore. By this means I am
enabled to make the said insulating pieces of different lengths in such a manner that
I can employ any letter of the "Morse" alphabet and thus greatly increase the
number of possible combinations of signals, and the distinctive character of the
said signals.
Another important feature of my said invention is the provision of means for
automatically offecting the return of the index or pointer, after it has been moved
to any of the signals upon the dial, to the signal for a messenger, or to any other
predetermined frequently employed signal, and also the return of the brush or
contact arm.
I provide moreover improved means for diverting or shunting the electric current
that is to say permitting it to pass through the apparatus to line without passing
through the brush or contact arm and signal disc or wheel when the apparatus is at
rest, thus short-circuiting the said contact arm and signal disc or wheel.
My said invention comprises, moreover, other improvements hereinafter set
forth.
In the accompanying drawings I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a front elevation."
Figure 2 is a similar view to Figure 1 the front portion of the box or casing and
some other parts being removed.
Figure 3 is a side elevation a portion of the box or casing being removed.
Figure 4 is a plan partly in horizontal section through the box or casing and,
Figure 5 is a rear elevation partly in section, illustrating an application of my
present improvements to a transmitter for electrical signalling apparatus.
Figure 6 is a horizontal section showing a detail of construction.
Figure 7 is a front elevation showing a signal wheel or disc with a different
arrangement of signals thereon.
Figure 8 is a front elevation showing another form of box or casing.
Like letters indicate corresponding parts throughout the drawings.
A is the box or casing B is the train of clockwork which may be of any well known
construction, B is the actuating spring thereof, B2 is the frame supporting the said
train of clockwork, C is the signal disc or wheel, D is the contact arm or brush,
E E' are the wires or cables for conveying the electric current to the apparatus, F is

page_text: the operating or actuating arm or lever for winding or storing energy in the spring
of the train of clock work.
Tho signal disc or wheel C is firmly secured to a spindle B forming part of the
train of clockwork B, which is so arranged that the said signal disc or wheel will
perform one complete revolution at each operation of the said clockwork. Instead of
insulating segments arranged in radial lines as described in the said former Specifi-
oation provide in the signal disc or wheel C insulating blocks or pieces a a a³ aª
arranged in groups in different concentric circles, ench of the said insulating pieces
being separato or isolated from the other as shown. I am thus enabled to form the
said insulating pieces if desired of different lengths (as shown in Figure 7) and thereby
extend the range of signals that can be made by the signal disc or wheel without
unduly increasing the diameter thereof. Moreover by forming the said insulating
pieces of different lengths a greater number of letters of the "Morse" alphabet can
be employed as already mentioned.
Instead of holes being formed right through the signal disc or wheel O and filled
with insulating or non-conducting materin!, recesses of any convenient depth may bo
formed in the said signal disc or wheel and filled with enamel or other suitable
non-conducting, or insulating material. In some instances I provide recesses or
spaces only.
The operating lever F for winding or compressing the actuating spring B' of the
train of clockwork B and storing energy therein is firmly secured to the main shaft
or arbor B of the said train of clockwork. b is a quadrant also firmly secured upon
the spindle B. The quadrant & is provided with a projection at either extremity
thereof (as more clearly shown in Figure 5) adapted to bear against a stop e secured
to the framing B and thus limit the movement of the said operating lever F in either
direction and consequently the amount that the actuating spring B' can be wound or
compressed when the said operating lever is moved in the direction indicated by the
arrow in Figure 1, and the amount that it is permitted to unwind or react at each
return movement of the said operating levor. This movement is sufficient to give one
complete revolution of the signal disc or wheel C at each operation. Motion is
imparted from the main shaft or arbor B and actuating spring B' to the train of
clockwork B in the usual or any suitable manner. The movement for storing energy
in the actuating spring B' of the clockwork is thus very advantageously governed or
regulated, and the operating lever can be more conveniently handled than when
placed at the side of the apparatus as described in the said former Specification.
"
The brush or contact arm D is pivoted at D' to the frame B' as hereinafter
described, and is so arranged that it is normally in line with or in the path of the
inner circle of insulating pieces a which preferably give the_signal for " messenger
or some other signal which is the most frequently in uso. For moving or adjusting
the brush or contact arm D so as to bring it in line with or in the path of either the
circle of insulating pieces a' a² or a which in this instance give the signal for "cab"
police" and
'fire" respectively, I provide upon the main shaft or arbor B a
sleeve d. d is a disc or collar firmly secured to or formed on the inner, or one
extremity of the said sleeve d. e is an index or pointer adapted to fit upon a square,
hexagon, or other suitably shaped portion provided upon the other, or onter extremity
of the said sleeve d and which is retained thereon by means of tho operating arm or
lover F. The said operating arm or levor is pinned or otherwise secured upon the
extremity of the said main shaft or arbor B which is arranged to project sufficiently
beyond the said sleeve for that purpose. fis an arm or lover secured to the brush or
contact arm D by means of a hollow screw f¹ (as more clearly shown in Figure 6)
through which the pivot D' passes, fare pieces or washers of non-conducting
material for insulating the said brush or contact. arm D. The free extremity of the
arm or lever fis coupled by means of a connecting rod g to the said disc or collar d'.
dis a tooth or projection upon the disc or collar d'. The said tooth or projection d
is adapted to engage with a pin or stop upon the frame B' when the brush or
contact arm D is in the path of the inner circle of insulating pieces a. h is a spring

page_text: for retaining the said disc or collar in this position. is a tooth or projection also
adapted to engage with the said stop d and limit the movement of the said disc d'
in the other direction. d d and d' are other teeth or projections upon the said
disc or collar d. i is a pawl or detent pivoted at to the frame B. One extremity
of the pawl or detent i is adapted to engage with one or other of the said teeth or
projections d d and d².
When the index or pointer e is moved opposite the word "cab" upon the dial or
casing A, the disc or collar d' will be also moved into such a position, through the
sleeved connected with the said index or pointer, that the pawl or detent i will
engage with the tooth or projection d³, and the brush or contact arm D will be
adjusted through the connecting rod and arm or lever so as to be in the path of
the circle of insulating pieces a. When the index or pointer is moved opposite the
word "
police" the said pawl or detent will be engaged with the tooth or projection d
and the said brush or contact arın be in like manner adjusted in the path of the
circle of insulating pieces a³, and when the said index or pointer is moved opposite
the word "fire" the said pawl or detent will be engaged with the tooth or projection d
and the brush or contact arın be placed in the path of the circle of insulating pieces a*.
jis a pin or projection upon the signal disc or wheel which is adapted at or near
the termination of the rotary movement of the latter, and after the contact arm bas
passed the last of the insulating pieces, to ongage with an inclined surface provided
upon the long arm, or one arm of the pawl or detent lever i, and raise or trip the
latter so as to disengage the short arm, or other arm thereof from whichever of the
teeth or projections d d or d' with which it may have been engaged. Thus
permitting the said disc or collar d¹ and pointer or index e to return to their normal
position under the action of the spring h; and through the said connecting rod g
and arm or leverf, bring the brush or contact arm D back into the path of the
circle of insulating pieces a.
I thus provide very advantageous, simple, and effective means for automatically
bringing back or returning the said brush or contact piece D, and index or pointer e
after each operation of the signal disc or wheel C to a predetermined and frequently
required signal. The risk which would otherwise occur of the apparatus being left
set for "police'
""fire" or some other signal which is comparatively but seldom used
after the dispatch of the said signal, and being again inadvertently operated without
changing or adjusting the apparatus back to the signal usually most employed is
thus obviated.
k is a rod one extremity of which is attached to the long arm of the pawl or
detent lever i. The rod k passes through a suitable hole provided in the box or
casing A and has upon its free extremity a knob k¹. By ineans of the rod k the
pawl or detent lever i can be tripped or disengaged from either of the teeth upon
the disc or collar d' by hand, when it is desired to return the latter to its normal
position without operating the apparatus.
The wire or cable E is electrically connected at to the box or case A, and the
wire or cable E is electrically connected to a bolt m suitably insulated from the said
box or case. The bolt m is electrically connected by means of a wire or wires n to
the upper extremity of the brush or contact arm D, and by means of a wire or
wires n' with a contact spring o firmly secured to the frame B' so as to be in
electrical connection therewith. 6 is an extension upon the quadrant 6, which is
adapted under normal conditions to form or make contact with the said contact
spring o thereby short circuiting the brush or contact arm D and the signal disc
or wheel C, so that the electric current which naturally follows the easiest path
passes through the said frame B' and the box or case A to line without_passing
through the said brush or contact arm D and signal disc or wheel C. When however
the operating lever F is moved to wind, or compress the actuating spring B' of the
clockwork B, the quadrant b is also moved as hereinbefore described, and consequently
the contact between the said contact spring o and the extension 6' is broken and the
circuit through the wire or wires n³ being interrupted the electric current is forced

page_text: to pass through the wire or wires n, the brush or contact arm D, and the signal disc
or wheel C to the frame B', box or case A, and line. The deterioration of the
extremity of the brush or contact arm D from galvanic action is thus obviated or
reduced to a minimum.
The operating arm or lover F and the indox or pointer e are provided with suitablo
knobs or handles F and e' formed of any suitable non-conducting
torinl.
The front part of the box, or case, or dial or a portion thereof is formed of glass,
or other suitable transparent material, and a suitable hole is provided therein through
which the shaft or arbor B and the sleeve d project, the horvinbefore mentioned
operating lover F and the pointer or index e being secured to the said shaft or arbor
and sleeve upon the outside of the box or caso A. By means of this window or
transparent portion, the operation of the apparatus can be seen and any failure thereof
ascertained.
The box or case A is preferably constructed in two parts and is so arranged that
it can be readily opened for inspection of, or repairs to the internal mechanism.
A' A' ara tubular pieces formed of any suitable non-conducting material and secured
in the said box or case A. Serows or the like may be passed through the said
tubular pieces for socuring the apparatas in position upon any convenient support.
A is a block or piece of wood or other suitable material for convenience of securing
the wires or cables E E¹.
The operation of the apparatus is substantially similar to that described in the
Specification of the said former Letters Patent.
Figure 8 illustrates another form of box or casing wherein the directions and other
printed matter are cast in relief, and the said box is of an oval or elongated form.
Suitable lugs A are in this instance moreover provided upon the outside of the box
or casing A in which are secured the tubular pieces A' so that the apparatus may
bo fixed in position without removing the cover, thus obviating any chance of injury
to the mechanism during the said fixing.
It is obvious moreover that I can somewhat further modify the construction of
my improved apparatus without departing from the nature of my said invention.
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:-
First. An electric signal-transmitter, wherein provision is made for controlling or
determining the signals by the adjustment of a brush or contact arm relatively to
concentric series of insulating pieces or spaces on or in a rotating disc of conducting
material, for the purposes above specified.
Second. In or for an electric signal-transmitter, the disc or wheel of conducting
material provided with the separate insulating pieces or spaces arranged concentrically
in groups, substantially as, and for the purposes, specified.
Third. The improved means whereby the brush or contact arm may be adjusted
relatively to the concentric series of insulating pieces or spaces upon or in the signal
disc or wheol, and will bo automatically returned to a predetermined position after
cach operation of the transmitter substantially as described.
Fourth. The improved means comprising the contact piece or spring and the arm
or projection substantially as described, for short circuiting the brush or contact arm
and disc while the apparatus is at rost, as, and for the purposos above specified.
Fifth. The improved moans substantially as above described for storing energy in
the actuating spring and for limiting or regulating the amount of energy thus stored,
for the purposes specified.
Sixth. The combination, with the contact arm or brush and the index or pointer,
of the improved device for returning the same to their normal position by hand,
substantially as described.
Soventh. A signal-transmitter having the improved box or casing substantially as
described with reference to Figure 8 of the accompanying drawings.

page_text: Eighth. The improved signal-transmitter constructed substantially as described
with reference to Figures 1 to 6 of the accompanying drawings and operating as,
and for the purpose, hereinbefore specified.
Dated this 10th in 1900
ROBT. DUNBAR RADCLIFFE.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.