IMPROVEMENTS IN ELECTRIC BELL APPARATUS FOR SIGNALLING IN HOTELS AND OTHER BUILDINGS AND PLACES
Year: 1874

page_text: LETTERS PATENT to Peter Jensen, of 89, (Chancery Lane, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN
ELECTRIC BELL APPARATUS FOR SIGNALLING IN HOTELS AND OTHER BUILDINGS
AND PLACES." -A communication from abroad by Gustaf Adam
Wiman, of Stockholm, Sweden.
Sealed the 13th April 1875, and dated the 14th October 1874,
PROVISIONAL SPECIFICATION left by the said Peter Jensen at the
Office of the Commissioners of Patents, with his Petition, on the
14th October 1874.
I, PETER JENSEN, of 89, Chancery Lane, in the County of Middlesex,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN ELECTRIC BELL APPARATUS FOR SIGNALLING IN HOTELS AND OTHER BUILDINGS
AND PLACES, (a communication to me from abroad by Gustaf Adam
Wiman, of Stockholm, Sweden,) to be as follows :-
"
-
In electric bell apparatus for hotels and other buildings and places it.
has heretofore been usual to employ a special electro-magnet for each

page_text: room in communication with such apparatus, and the signal is indicated
on a dial, the number in question being thrown forward direct from its
corresponding electro-magnet: Now according to this Invention the
same effect is produced by means of one electro-magnet in combination
with a smaller driving gear, which latter also takes the place of
the electric striking apparatus used in number apparatus of older
construction.
The driving and striking gear are placed in the front part of the
apparatus; the driving gear may be actuated by weight or spring, and is
of usual construction.
By means of a tooth wheel on the main spindle at the centre part o
the apparatus motion is transmitted to a pawl wheel, which gives
pendulous motion to an escapement-like lever that has two arms with
hammers or balls for striking the bell, the said arms also serving to
regulate the motion, and a fork on the lever in combination with a stud
fixed between the sides of the fork serves to the further regulation of
the movement.
-
The main spindle has at the back a double arm fastened to it, which
arm at one end operates against contact springs (about which, later on),
while the other end, by a fork joint, is connected to a dial hand rotating
with the main spindle, and having also a motion at right angles to the
plane of rotation by means of a bell-crank lever attached to the keeper
of an electro-magnet. When the apparatus is at rest, and a spring holds
the keeper back from the electro-magnet, the hand rests against a stop,
thus preventing the motion of the driving gear; but when the keeper is
attracted the hand is released from the stop.
f
The electro-magnet rests on the back of the case, its wire end is
carried to the metal case, and the other end passes by an insulated stud
to a pinching screw connected to one pole of a battery. The electro-
magnet is surrounded by a wooden ring, in the circular front recess of
which contact springs are fastened, each of which is connected by' means
of wires to a pinching screw in connection with the battery; the wires
leading to the different rooms are attached to the said pinching screws.
When the apparatus is at rest the contact springs rest against stops,
which are insulated from the apparatus but connected with each other
and with a main contact spring, but not with the aforesaid insulated
stud, from which it is kept by the lower end of the aforesaid double

page_text: arm. It comes in contact only when the apparatus is at work; that is,.
when the said double arm has commenced rotating. The said lower end-
of the double arm has also the office to insulate for a moment each of
the other contact springs in succession from the common connection in
a metal ring placed in the front recess of the aforesaid wooden ring,
The metal ring carries a series of spindles which can turn, and which at
their front end carry each a disc with a signal number or letter, which
by the turning of any of said spindles are brought opposite corresponding
openings in the dial, and thus made visible. These signal spindles are
rotated when the outer end of the hand comes in contact with a lever or
catch fixed to each spindle; there are stops to limit the extent of the
rotation. The spindles pass through holes in the metal ring, and are
here held in wire eyes, which also tend to act as brakes on their
rotation; the spindles are carried back to their original position
by means of pegs on a ring, which is rotated by the double arm
aforesaid.
•
•
J
The action of the apparatus is as follows:-Say room No. 4 sends a
signal by depression of a contact knob, the current passes from the
corresponding pinching screw to the corresponding contact spring which
leads it on to the corresponding stop, thence to the metal ring and to the
main contact spring, thence through the double arm to the metal body
of the apparatus, where it meets the wires of the electro-magnet, and
thence passes through the insulated stud and to one of the poles of the
battery. The keeper of the electro-magnet is meanwhile attracted, the
hand gets free of its stop, and the driving gear commences to work; but
as soon as the double arm lets go the main contact spring, this latter
comes to rest against the insulated stud, and the current goes from the.
main contact spring and the insulated stud direct to the pinching screw
and the battery. The keeper will thereby be let go, and the outer end
of the hand can freely pass the small levers or catches on the signal.
number spindles. As soon as now the double arm, during its rotation, :
has in succession bent the contact springs out of the way, and has got.
to the spring No. 4, which thereby has got released from its stop, the
current is prevented from going from that spring and its stop to the
metal ring, and must on the contrary pass through the double arm, the
centre spindle of the apparatus, the coils of the electro-magnet, and the
insulated stud back to the battery. The keeper is then again attracted,
the outer end of the hand is pushed back, the lever on the spindle No. 4

page_text: is hit by the hand; the spindle makes a quarter of a turn, and the
number 4 on its end disc appears in the hole of the dial. The hand is
then arrested by the stop No.4 at the spindle No. 4; the driving gear
is made to stop so long as the contact knob in room No. 4 is depressed,
or until another room sends a signal.
Supposing room No. 3 sends a signal at the same time, then the
current would go through the spring No. 3 and stop, to the metal ring
through the main contact spring, the insulated stud, and to the battery.
The keeper is released, the hand is released from the stop No. 4 and
continues its movement till it stops, whereupon the spring No. 3 acts in 1
a similar manner as described with reference to No. 4. The same would
be the case if all the rooms sent signals simultaneously; the hand would
then go from number to number and turn the spindles till all signal
numbers were displayed.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Peter Jensen in the Great Seal Patent Office
on the 14th April 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
JENSEN, of 89, Chancery Lane, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of October, in the year
of our Lord One thousand eight, hundred and seventy-four, in the
thirty-eighth year of Her reign,, did, for Herself, Her heirs and suc-.
cessors, give and grant unto me, the said Peter Jensen, Her special
licence that I, the said Peter Jensen, mỹ executors, administrators,
and assigns, or such others as I, the said Peter Jensen, 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 make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland; the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
ELECTRIC BELL APPARATUS FOR: SIGNALLING, IN HOTELS AND OTHER BUILDINGS
AND PLACES," (a communication to me from abroad by Gustav Adam

page_text: spindle transmits motion to the escapement wheel S", which by one
-revolution causes the escapement S¹, S', to be put into a forward and
backward motion; on the escapement -St, S¹, there are two arms with
their hammers or balls S¹¹¹, which by the movement of the escapement
are caused to strike the bell B'; the escapement mechanism thus both
-regulates the motion and strikes the bell. The small fork X¹ proceeding
from the centre of the escapement fork works against a stud X" and
serves to the further regulation of the movement.
.
The main spindle e has at the rear part of the apparatus a double
arm V, V¹, fastened to it, which arm, at one end V operates against the
contact springs 1, 1, 2, 2, 3, 3, and so on, while the other end V, by a
fork joint and pin 7, is connected to the dial hand V, V, which
rotates with the main spindle e, but has also a motion at right angles to
the plane of rotation; this motion is communicated to it by means of
the peg / from the bell-crank lever fattached to the keeper C of the
electro-magnet A. When the apparatus is at rest, and the spring fi
holds back the keeper C, which is movable on the spindle f¹, from the
electro-magnet A, the dial hand takes the position shown, resting against
a stop d, Fig. 2, and the movement of the driving gear is thus “pre-
vented; but when the keeper O is attracted by the electro-magnet,
the hand is released from the stop d and movement can then take
place.
The electro-magnet rests on the back of the case; its wire end A²,
Fig. 2, is carried to the metal mass of the case, and the other end A
passes by the insulated stud a to the pinching screw B connected to
one pole of the battery. The electro-magnet A is surrounded by a
wooden ring R, in the circular turned front recess of which the contact
springs are fastened, each of which is connected to a pinching
screw 1, 2, 3, &c., by means of wires laid in the wooden back of the
apparatus; the wires leading to the different rooms are attached to the
said pinching screws. When the apparatus is at rest, the contact
springs rest against the stops a¹, a², a³, &c, which are insulated from the
metal mass of the apparatus, but by the metal ring S connected with
one another and with the main contact spring 12, 12, but not with the
insulated stud a; the spring 12, 12, is kept away from the stud a" by
the arm V, and comes in contact only when the apparatus is at work,
that is, when the double arm V, V, has commenced rotating. The
arm V, V₁, has the double office, that it while in a state of rest keeps
t

page_text: the spring 12, 12, away from the stud a¹, and that it, that is, its lower
end, while at work insulates for a moment each of the other contact
springs in succession from the common wire connection in the metal
ring S. Placed in the recess of the wooden ring a series of spindles m²;
m³, m³, &c., are fitted so as to turn one end in the metal ring T which
fits on the wooden ring on the block R; these spindles carry at their
front ends each a disc 1, . By turning the spindles the discs aré
pushed forward into openings y in the large dial ġ by the ciphers
marked thereon, and thus indicating from which room a signal has been
sent. The spindles are set in motion when the end of the hand V, V
comes in contact with a lever or catch g¹, 9", fastened on each spindle:
The width of these catches is such that the hand can pass it without
hindrance when its point during the rotation is at the greatest distance
from the wooden ring, but when it by means of the keeper C is brought
the least near to the ring then it comes against the catches 9¹, 9", and
turns the spindles with their discs one quarter turn round. The wooden
ring has also fixed stops, 3, 3, &c., the width of which is equal to the
diameter of the spindles; their object is to stop the hand, and thus the
whole mechanism after the hand has turned a spindle with its disc.
The upper ends of the spindles m², m³, m³, &c., lie in open notches in
the metal ring U, and are kept therein by the metal wire p, p, which
also serves to brake them so as to retain them in any position. The
spindles are carried back to their original position by means of pegs on
à ring X, which can be rotated by means of the arm y", the pegs on the
ring taking against the ends " of the catches g³, g¹¹.
The action of the apparatus is as follows:-Say that the room No. 4
sends a signal by depression of its contact knob, the current then passes
to the contact springs 4, 4, which through the peg a transmits it to the
metal ring S and the spring 12, 12, whence the current is led by the
arm V to the metal mass of the apparatus; the current there meets
the wires of the electro-magnet, passes through them and passes back
through the wire A" and stud a¹ to the pinching screw B and one of
the poles.of.the battery... The keeper of the electro-magnet is meanwhile.
attracted, the hand V, V, gets free of its stop d, and the driving gear.
commences to work. The keeper will thus of course at once be released
from the electro-magnet, and the outer end of the hand V, V, can
freely pass the small catches g¹, g¹.. As soon as now the arm V, during
its rotation has in succession bent the contact springs 1, 1, 2, 2, 3, 3, out:

page_text: of the way and has got as far as the spring 4, 4, which thereby has got
released from its stop, the current is prevented from going from the
spring 4, 4, by its stop at to the metal ring S¹, and must on the contrary
pass through the arm V, the metal body of the apparatus, the coils of
the electro-magnet, and the stud a back to the battery. The keeper is 5
then again attracted and the outer end of the hand is pushed back to
its smallest distance from the wooden ring. The catch on the spindle m
is now hit by the hand, the spindle-makes a quarter of a turn and the
one half of the disc l, l, comes opposite the round opening y* at the
number 4. The hand is then arrested by the stop ", the driving gear is 1
made to stop and remain at rest as long as the contact knob in room
No. 4 is depressed, or until another rooms sends a signal.
•
If it be desired to have the apparatus ringing all the time that the
contact knob is depressed, then that may be attained very simply by
removing the stops i, 2, 3, &c., and by leading the wire end A" of the 1
electro-magnet direct to the screw B without touching the stud a". By
this latter arrangement the advantage is also gained that, supposing
signals be sent simultaneously from several rooms, the hand in a single
revolution throws up the discs for all the rooms in question.
And having thus fully described the nature of this Invention, and 2
the manner in which the same is or may be carried into effect, I will
now set forth some of the main advantages of this apparatus as compared
with apparatus of older construction,―
1. Greater cheapness in the production of the apparatus.
2. Greater accuracy, which is simply gained by the employment of a 2
very good electro-magnet, which does not appreciably increase the
cost of the apparatus. To attain the same result in the ordinary
apparatus, not one but a whole number of electro-magnets would have
to be replaced.
3. From the same same reason, less trouble and expense in keeping 3
the battery in proper order, and less susceptibility to the influence of
inequalities in the strength of the current, whether owing to the battery
or to incomplete insulation.

page_text: 7. That the clockwork in this apparatus (unlike other apparatus
with driving gear and used for bell signals only) does not run just
so long as the knob is depressed, but stops as soon as the number
of the room whence the signal came has been displayed, thus
avoiding complicated gearing or frequent winding up of the driving
gear.