IMPROVEMENTS IN APPARATUS FOR ACTUATING DOMESTIC BELLS AND OTHER SIGNALS BY THE ELECTRIC CURRENT."
Year: 1863

page_text: LETTERS PATENT to Andrew Edmund -Brae, of Leeds, in the County, of
York, for the Invention of "IMPROVEMENTS IN APPARATUS FOR ACTUATING
DOMESTIC BELLS AND OTHER SIGNALS BY THE ELECTRIC CURRENT."
PROVISIONAL SPECIFICATION left by the said Andrew Edmund Brae
at the Office of the Commissioners of Patents, with his Petition, on
the 24th June 1868.
I, ANDREW EDMUND BRAE, do hereby declare the nature of the said Inven
tion for "IMPROVEMENTS IN APPARATUS FOR. ACTUATING DOMESTIC BELLS. AND
OTHER SIGNALS BY THE ELECTRIC CURRENT," to be as follows:-
In my improvements the electric current being put into action by touch in
the usual way, traverses the coil of an electro-magnet, causing it to attract.
an armature and withdraw a detent, whereupon an arm or lever falls by its
own gravity from a nearly vertical to a horizontal position, and so indicates.
in a very conspicuous manner the place or person whence the call, of which
notice is at the same time given by a bell or other signal, has proceeded. I
do not claim any novelty in this mode of displaying an indication, excepting
in so far as it is rendered more practicably useful by my peculiar arrangement.

page_text: in combination with my other improvements. The indicating arm projects
from a central boss or pulley with which it revolves, and which has round it a
chain or band to form a pull by which the arm may be again set up by an
attendant at the same time that its indication is noticed. Upon the central
boss are ridges or cams for the purpose of producing automatically by the
motion of the arm certain changes in the course and direction of the electric
currents. By these changes I obtain various effects. Instead of actuating
the bell by the same current that acts upon the indicator, or by any branch
from or continuation thereof, I make use of separate and distinct means for
that purpose, either by causing the arm to strike a bell during its descent
or by causing it to establish, by means of the cams aforesaid, an independent
current from the battery to tho bell. Hence I avoid charging the same
current with different incompatible functions, and I desire that this separation
and isolation of the indicators from the bell be regarded as a distinguishing
feature of my Invention.
Another distinguishing feature of my Invention is the method of causing
the indicating arm to effect automatically by its motion from one position to
another changes and transfers in the course of the electric current.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Andrew Edmund Brae in the Great Seal Patent Office on
the 23rd December 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANDREW.
EDMUND BRAE, of Leeds, in the County of York, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of June, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Andrew Edmund Brae, Her special licence that I, the said Andrew
Edmund Brae, my executors, administrators; and assigns, or such others as I,
the said Andrew Edmund Brae, my executors, administrators, and assigns;
should at any time agree with, and, no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully might
makė, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "Iк-
PROVEMENTS IN APPARATUS FOR ACTUATING DOMESTIC BELLS AND OTHER SIGNALS BY
THE ELECTRIC CURRENT," upon the condition (amongst others) that I, the said

page_text: Andrew Edmund Brae, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immédiately after
the date of the said Letters Patent.
"
NOW KNOW YE, that I, the said 'Andrew Edmund Brae, do hereby
declare the nature of my.said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement :--
In my improvements the electric current being put into action by "touch"
in the usual way, traverses an electro-magnet, and causes it to attract an
armaturo and withdraw a detent, whereupon an arm or lever falls by its own
gravity or the impulse of a spring from a nearly vertical to a horizontal
position, and by that or any other remarkable change of position conveys a:
conspicuous indication. of the place or person whence the call, of which notice
is at the same time given by a bell or other signal, has proceeded.
I do not claim any novelty in this mode of displaying an indication,
excepting in so far as it is rendered more practically useful by my peculiar
arrangement of it in combination with my other improvements. The indi-
cating arm projects from a central boss or pulley with which it revolves, and
which has round it a chain or band to form a pull, by which the arm may be
again set up by an attendant at the same time that its indication. is noticed.
Upon the central boss are ridges or cams for the purpose of producing auto-
matically by their action upon commutating springs.certain changes in the.
course and direction of the electric current. Now a slight consideration of
this description of central boss, projecting arm, and pulley chain will shew.
that it is exactly embodied in a common and well known apparatus called a.
"bell lever," the only difference being in the manner of using; that is to say,
instead of the chain being pulled to elevate the arm as above described, in
ordinary use the arm or lever is moved in order to act upon the chain.
My object in assimilating my indicator to the bell. lever has been to
take advantage of the readiness and cheapness, with which that article may
be procured, the slight alteration by which it may be adapted to all.
the requirements of a good indicator, its. substantial and excellent.manu-
facture, its finished and ornamental appearance, the remarkable distinctness.
imparted to its indication by the white porcelain knobs with which it is.
ornamented, and the facility they afford for the inscription thereon of indi..
cating numbers, and lastly, the similitude which a number of such indicators

page_text: when ranged in series. may be made to bear to the ordinary and familiar
appearance of ranges of bells on the old system of bell hanging. (see Fig. 5.in
the Drawing)...
.
.:.
: In.the general arrangement of my apparatus I. also adopt the bell lever for
the "touch,".or.the means by which action is given to the electric current by
the person sending the call. For that purpose I do not pull upon the chain,
but I make.usé of the handle or lever in the ordinary way, reaction being
provided by a helical spring attached to the chain. Upon the lever.being
depressed by hand in the usual way, a cam upon the centre boss, exactly
similar to that upon the indicator, acts upon a concealed spring touch within
and completes the electric circuit. When I fit up a lever pull in this way
for
the interior of an apartment it differs in no respect either in outward
appearance or in the manner of using from an ordinary domestic bell, so
that no previous explanation respecting it need be given to the occupier of the
apartment.
Having described the exterior form of my apparatus, and the advantages I
obtain by the adaptation of the bell lever, I now proceed to describe the
interior alterations and additions which I make in it in order to commute and
preserve distinct the course of. the electric current in its several functions. of
indicating, ringing, and if need be of returning an answering signal to the
caller in assurance of attention.
"
In the annexed Drawings the Figures 1, 2, 3, 4, and 6 are of the full size
of the apparatus; Figure 5 is of half that size.
.
.
Figure 1 represents the reverse or under side of the central boss of my
ordinary bell lever. It is usually of iron, but may be of any material ;* a
portion of the interior edge is cut away (from a to 6), so as to form a cam or
elevator at the point a, for the purpose of raising the tongue of the commuting
spring. D is the under side of the lever arm terminated by a knob of
porcelain, and C is the depending chain, which may be lengthened to any
required extent, so as to be within convenient reach of the attendant, and by
pulling which the central boss is caused to revolve, by which the exterior
lever and interior commutator are simultaneously raised..
1
Figure 2 represents the iron cup or socket, within which the boss revolves.
upon its centre pin. The socket is cut away at the side (or left open in
casting), for the purpose of admitting the commuting spring or springs here-
after described. The socket is sunk into a base-board in the usual way, and
the base-board is also cut away at the side, as shewn at A, for the purpose of
receiving and protecting the commutator.
Fig. 3 represents the socket and the commutator in their respective positions.

page_text: A is a flat plate of boxwood or other insulating substance, into which are
fixed the spring B, and the two contact studs c and d. The spring B is so
set that it always bears upon the lower stud c, and except when lifted by the
cam into contact with the upper stud d. Now the spring B being in metallic
connexion. with the wire conveying the electric current from the person sending
the call, and the stud d-being in connexion with the coil of the electro-magnet
of the detent, it follows that so long as the lever arm remains in a vertical
position, with the spring B consequently in contact with stud d, the electric
current: sent. from the caller first flows exclusively to the detent and releases
the lever, the falling of which immediately transfers the commuting spring to
the lower stud e, which being in connexion with the coils of an electric bell,
the transferred current then acts exclusively upon the said bell, and the call
may be reiterated until attended to. Thus the current of electricity has only
one function to perform at the same time, and no embarrassment from inter-
mixture of effect.can take place. When in addition to this simplest form of.
my indicator I require an answering indication from the attendant, to the
caller, I provide for it by an additional spring and two additional contact studs
upon. the same boxwood plate, as represented in Fig. 4, wherein A, as before,
is the boxwood plate; B and C, two similar commuting springs, and c, d,
e, f, four contact studs. The upper spring C is in connexion with the wire
coming from the caller; it rests upon the contact stud e, which is in connexion
with the lower spring B, which acts between its own studs ċ and d; precisely
as has been already described for Fig. 3. But when the spring B'is over
raised by the cam, that is, when it is raised more than enough to place it in
contact with its studd, it comes in contact with the insulating button which
may be observed at the extrémity of the upper spring C, and thereby raises it
also from stude into contact with stud f. The effect of this last commutation:
is to disconnect the wire coming from the caller with everything except stud f,
which being in connexion with the positive pole of the galvanic battery
becomes capable of sending back through the wire of communication between
caller and 'attendants an answering or return current, provision for its reception
being provided at the caller's end by similar commutation. Now the extra
lift necessary to reach the upper spring is effected by setting back the vertical
stop of the lever arm a little further than would be required for placing it
behind its detent; and as the attendant in pulling 'back' the indicator naturally
will do so until it comes. against. the stop; he will unconsciously send back
an answering signal audible or visible within the apartment of the caller.
Independently of the office of returning answers to calls there is another
service for which this part of my apparatus.is applicable, 'and which I claim as

page_text: a great advantage. By the provision of the small extra space just described,
between the latching of the detent and the final stop, the lever may at any
time be pulled back to that extent and resume its position without any other
disturbance of the indicator. Hence it may be used to transmit independent
calls from the attendants to any of the several chambers, and hence, in hotels
for example, each individual indicator may be used for the purpose of arousing.
the occupier of the apartment to which it belongs.
Fig. 5 is a general representation of the appearance of these indicators in
series with their consecutive numbers conveniently and conspicuously painted
upon their larger porcelain knobs.
..'
Fig. 6 is a full sized view in detail of one of the numbers in the above
series, showing the electro-magnet, the armature and latch detent, and the
several stops and connexions omitted from the' general view; C, C, is the coil
of the detent magnet; D is its soft iron core, one leg of which is prolonged
for the purpose of serving as a support for the armature E, which vibrates
upon a pivot passing through bolts; F is the smaller porcelain knob of the
lever broken. away at the edge to show the detent pin and catch beneath;
G is the cover of the commutators; H is the vertical stop; N, L, P, B,' are
four screws with, copper washers serving to connect the several wires. and
secure them to the base-board, of these N has ultimate connexion with the
negative pole of a galvanic battery, P with its positive pole, L with the line
wire between caller and attendant, and B with an. electric bell common to
the whole series.
Now one of the advantages I obtain by commuting the electric current
into two separate and distinct functions is the power of using for the coil of
the detent magnet a much coarser, shorter, and consequently cheaper coil
than is necessary for that of the bell, an advantage unattainable when the
coils of both indicators and bell are simultaneously excited by the same current
passing through both, in which case the coils must be equal and similar to
obtain anything like equality of effect or certainty of action.
I therefore claim as my Invention the principle of successive and separate
action in the electric current when applied to the double function of indicator
and 'bell for domestic purposes, whether the same be carried out in the precise
manner set forth herein, or by any other means for producing a similar effect,
as, for example, by placing the commuting springs and studs in some other
situation, and causing them to be acted upon by the exterior lever instead of
by the interior boss.
I also claim as my Invention the general arrangement and combination of
known contrivances herein described and represented, together with the.

page_text: application of the common bell lever to the purpose of an indicator for the
attainment of the several advantages set forth and explained.
In witness whereof, I, the said Andrew Edmund Brae, have hereunto
set my hand and seal, this Twenty-second day of December, in the year
of our Lord One thousand eight hundred and sixty-three.
ANDREW EDMUND BRAE. (L.S.)