IMPROVEMENTS IN PNEUMATIC TELEGRAPHIC APPARATUS
Year: 1880

page_text: LETTERS PATENT to William Morgan-Brown, of the Firm of Brandon and
Morgan-Brown, Engineers and Patent Agents, of 38, Southampton Buildings,
London, and 1, Rue Laffitte, Paris, for an Invention of "IMPROVEMENTS IN
PNEUMATIC TELEGRAPHIC APPARATUS." A communication from abroad by
Count George de Monti, of Paris, France.
PROVISIONAL SPECIFICATION left by the said William Morgan-Brown at
the Office of the Commissioners of Patents on the 28th February 1880.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown,
Engineers and Patent Agents, of 38, Southampton Buildings, London, and 1, Rue
[A
Laffitte, Paris. "IMPROVEMENTS IN PNEUMATIC TELEGRAPHIC APPARATUS."
communication from abroad by Count George de Monti, of Paris, France.
This Invention refers more particularly to that class of signals worked by
compressed air, generally used in hotels or private houses to summon domestics or
other persons into the different apartments with which the apparatus is connected
by a separate tube for each. The compression of the air produced by a pressure
upon a button or other similar well known arrangement at the further or receiving
end of each tube, and transmitted by such tube to the signal apparatus acts upon
a plate covering the delivery end of the tube in such manner as to lift the said
plate to a small distance. There are arranged in the apparatus as many such plates
as there are conducting tubes, the opening of each tube being covered by a plate.
All these plates are strung on a single fixed shaft in such manner that each of
them can lift independently from the others as soon as it receives the pressure of
the air transmitted by its tube. Each of these plates carries an arm which bears
against a lateral projection of a horizontal pin, the front end of which is engaged
under a raised part of a vertical sliding plate so as to hold up this plate, which
carries on its front face the number or other mark corresponding to the apartment
with which connects its respective tube. The horizontal pins holding up the
numbered plates are acted upon by springs, which have a constant tendency to
hold the said pins engaged with the raised parts of the numbered plates.
As soon as one of the swinging plates is lifted by a compression of the air in the
tube which it covers, its arm bearing against the projection of the horizontal pin
pulls back the latter to a small distance against the force of the spring and thus

page_text: liberates the corresponding numbered plate, which in consequence of its gravity
drops down and exposes its number to view.
In order to give audible notice when a signal has been transmitted an alarm is
connected with the apparatus, which consists of a train of clock work actuated by
a spring, and with the anchor of which is connected the hammer which strikes the
bell or bells. Ordinarily the movement of this clock work is arrested by an arm
which reaches under a projection formed on one of the shafts of the clock work,
and which thus arrests its rotation. This arresting arm is mounted on a shaft,
carrying a second arm, on the extremity of which is attached a pusher piece against
which bears a suitably shaped arm, extending from a rock shaft arranged above
and running parallel with the shaft on which swing the plates covering the tube
openings. This alarm rock shaft carries furthermore a set of arms, corresponding
in number to the swinging plates, and so bent that each one of these arms rests
upon one of the swinging plates. It follows from this arrangement that as soon as
one of the swinging plates is lifted by the compression of the air in its tube
whereby, as above described, the corresponding number plate is liberated and
exposed to view, the said rockshaft through its arm resting upon the swinging
plate is turned slightly upward, thus imparting a corresponding movement to the
pusher piece, which in its turn liberates the arresting arm from the projection on
one of the shafts of the clockwork, so that the latter commences to move and sounds
the alarm. Immediately after having liberated the clockwork the pusher piece
comes back to its original position, and presents again the arresting arm in position
to be struck by the projection on the shaft of the clockwork when this shaft has
completed a revolution whereby the sounding of the alarm is stopped.
In order to bring back the numbered sliding plates into their original position
after they have been liberated and exposed to view, a shaft is arranged behind the
same on which a pin projecting backward from each of the said plates comes to rest
when the plate has dropped down; this shaft. can be bodily lifted upwards in
suitable slots formed in the framing by means of links, which connect it to cranks
of another shaft that may be partly turned by means of a handle outside the case
of the apparatus. It will be understood that the elevation of the said linked shaft
raises any of the numbered plates which may have dropped, and engages them again,
with the sliding pins serving to hold the same in their elevated position and to
liberate them at the moment when a signal is given.
The spring actuating the alarm mechanism is wound up from time to time by
means of a key like the spring of a clock.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Morgan-Brown in the Great Seal Patent Office on the
28th August 1880.
WILLIAM MORGAN-BROWN, of the Firm of Brandon and Morgan-Brown,
Engineers and Patent Agents, of 38, Southampton Buildings, London, and 1, Rue
Laffitte, Paris. "IMPROVEMENTS IN PNEUMATIC TELEGRAPHIC APPARATUS." A
communication from abroad by Count George de Monti, of Paris, France.
This Invention refers particularly to that class of signalling apparatus which is
worked by compressed air, and which is generally used in hotels and private houses
to summon domestics or other persons into the different apartments with which
the apparatus is connected by means of a separate tube for each. The compression
of the air produced by a pressure upon a button or other similar well known
arrangement at the further or receiving end of each tube, and transmitted by such
tube to the signal apparatus causes a number or other mark corresponding to the
apartment from which the current of compressed air has been transmitted to appear
at an easily visible part of the apparatus, and at the same time it causes an acoustic
signal to sound during a certain space of time in order to call immediately the
attention to the fact that a signal has been given.
In order to make the Invention better understood I will describe it conjointly
with the three Figures of the accompanying two Sheets of Drawings, in which―
Figure 1 is a front elevation in section of the signalling apparatus; Figure 2 is
an end elevation in section; Figure 3 is a front elevation; and Figure 4 is an end
elevation in section of a modified arrangement of one of the principal parts of the
apparatus.
All the parts of the apparatus are mounted on a vertical board 1, which may be
suspended on the wall or otherwise placed in an easily visible place. A case 2
hinged on one side to the board 1, and fixed on the other by means of a screw to
the said board, as shewn in the Drawing, encloses and protects the principal parts;
the face of this case consists of a plate of glass 3, the surface of which is rendered
opaque except on the spots where the numbers or other marks are to appear when
a signal is given. In order to cover also the upper parts of the mechanism the
case 2 is formed with a raised part 4, the face of which is closed by a hinged door 5
to permit the introduction of a key when it becomes necessary to wind up the
alarm mechanism.
On the board are mounted two or more brackets 6, which are connected with
each other by an iron strip 7, formed with holes or alots in which are introduced
the rubber tubes 8. These rubber tubes are connected to the metallic tubes 9 fixed
on the back of the board 1, and the bent ends of which project into the interior
of the case through holes formed in the board 1. The upper ends of these metallic
tubes are connected to the tubes 10, of rubber or other suitable material, which
establish the pneumatic communication of the apparatus with the different
apartments of the house. The rubber tubes 8 are formed each with a large flange
which rests upon the iron strip 7. The orifices of these flanges are closed by
means of plates 11 of thin sheet metal, which rests upon the flanges so as to
maintain an air tight contact with them. The plates 11 are free to oscillate, each
independently of the other, on a common fixed shaft 12, so that each of them can
lift slightly from its seat on the flange as soon as a pressure of air arrives through
the respective tube 8. Each of the plates 11 carries an arm 13, the upper extremity
of which bears against a projection 14, fixed laterally in the rear ends of the small
rods 15. These latter are adapted to slide horizontally in the arms 16, which
project backward from a metallic plate 17 mounted on the brackets 6. Spiral
springs 18, surrounding each of the rods 15, have a constant tendency to hold the
front ends of these rods projecting forward through holes formed in the plate 17.

page_text: The plates 19, carrying the numbers or other marks corresponding to the apart-
ments with which the apparatus is in communication, are arranged in vertical
slides 20 fixed on the face of the plate 17, and each of these numbered plates
carries on its rear face a projection 21, the upper side of which is inclined, and
under these projections the front ends of the rods 15 are engaged under ordinary
circumstances, so as to hold the numbered plates 19 elevated in the slides 20; but
as soon as a pressure of air arriving through one of the tubes 8 lift the plate 11
covering the opening of this tube, the arm 13 of this plate 11 pushes the rod 15,
which it controls, backward and liberates thus the corresponding numbered plate 19,
which then in consequence of its own weight falls in its slides 20, and exposes thus
its number through a transparent place in the glass 3.
The acoustic signal which accompanies every time the descent of one of the
numbered plates 19 is produced by the hammer 22 striking against the two bells 23
fixed on the arms 24, which are set in the metallic bands 25 on which the apparatus is
suspended. The hammer 22, as well as the escapement anchor, are mounted on a
shaft 26 of a train of clockwork 27, operated by a coiled spring, which has to be
wound up from time to time by means of a key introduced through the hinged door
of the case.
Above the shaft 12 on which turn the plates 11 and parallel therewith a shaft
28 is arranged capable of oscillating in its bearings, and on which are fixed a
number of arms 29, equal to the number of plates 11, and each of these arms rests
on one of the plates 11. The shaft 28 carries besides an arm 30, bent as shown,
and the end of which is engaged in a piece 31 hinged to the arm 32 on the shaft
33, which is mounted in the frame of the clockwork 27. This shaft carries a
pawl 34 which projects upward and prevents the movement of the clockwork by
its end being in contact with a projection 35 fixed on the shaft of the escapement
wheel; but the moment one of the plates 11 is lifted from its seat the arm 29
which rests on this plate imparts a slight oscillating motion to the shaft 28,
whereby the arm 30 is caused to push the piece 31 upwards, in consequence thereof
the shaft 33 is made to oscillate in its turn, and in this manner the pawl 34 becomes
disengaged from the projection 35 on the shaft 36 of the clockwork, the latter
becomes free to turn under the influence of the coiled spring of the clockwork and
causes the hammer 22 to operate. The movement of this hammer is steadied by
a fine spring 37. As soon as this result is obtained the parts controlling the pawl
34 return in consequence of their own gravity to their original position, and
when the shaft 36 has completed a complete revolution it is again arrested by the
pawl 34.
In order to limit the descent of the numbered plates 19, and in order to bring
them back into their original position each of them carries a pin 38 projecting
backward through vertical slots formed in the plate 17. When a plate descends its
pin 38 comes in contact with the rod 39 suspended by arms 40 on the cranks 41,
mounted on the oscillating shaft 42. By turning this latter in one direction by
means of the external crank 43 or by a cord 44 attached to this crank the shaft 39
is lifted, being guided in its movement in slots left open between the brackets 6
and the metallic pieces 45 interposed between these brackets and the plate 17.
The elevation of the shaft 39 causes through the intermediate pins 38 the metallic
plates 19 to be raised again; in this movement the projections 21 by means of their
inclined faces push the rods 15 slightly backward; the latter move forward again
immediately under the pressure of the springs 18, after the projections 21 have
passed their forward ends, and keep thus the plates 19 in the elevated position.
The shaft 39 is depressed as soon as the crank 43 is liberated by means of a spiral
spring 46 surrounding the shaft 42, and which tends to turn the latter in the
corresponding direction.
In the accompanying Drawing I have represented an apparatus capable of
receiving signals from four different rooms or apartments; but it is evident that
the apparatus may be constructed so as to communicate with a greater or smaller
number of apartments. For this purpose it is simply necessary to augment or

page_text: diminish to the desired number of communications the number of the numbered
plates and their operating means, as well as the arms bearing upon the plates 11
and projecting from the shaft 28, the arm 30 of which serves to operate the alarm
mechanism. Other modifications may be made in the details of the apparatus
without deviating from the principal of the Invention. Thus, in apparatus destined
to communicate with a great number of apartments it is possible in order to
prevent excessive length to arrange the parts operating the numbered plates, and
the latter themselves in two or more parallel series instead of arranging them in a
straight line, as shown in the Drawing; it is evident that this modification
necessitates modifications in the shape and arrangement of certain parts, although
the essential and characteristic features of the Invention are maintained.
In order to render more effective the action of the current of compressed air
arriving through the tubes 8, and which must act upon the liberating mechanism
of the numbered plates 19, as well as upon the liberating mechanism of the alarm
apparatus, I construct sometimes the tubes 8 with their flanges of a hard material,
such as metal, and cover the flanges with a thin sheet of rubber 47 bound over the
edge of the flange by means of a wire, as shown in Figure 4.
When a pressure of
air arrives in one of the tubes this sheet of rubber 47 swells out and lifts a light
plate 48 resting thereon, and which carries a rod 49, which by means of suitable
mechanical parts is connected to liberating mechanism of the plates 19 and of the
alarm apparatus which it is destined to operate.
Having thus described the nature of these improvements, as well as the best
method I am acquainted with of carrying the same into practice, I claim as the
Invention and desire to secure by Letters Patent,-
A pneumatic telegraph apparatus in which a pressure of air arriving through
suitable tubes operates a lifting plate, which in its turn acts through suitable
intermediate mechanical parts so as to expose to view a number or other mark,
indicating from whence the signal has come and at the same time to set in motion
an alarm apparatus driven by a coiled spring, and which is common to all the
numbers or marks contained in the apparatus, substantially as above described and
shown in the accompanying Drawings.
In witness whereof, I, the said William Morgan-Brown, have hereunto set my
hand and seal, this Twenty eighth day of August, in the year of our Lord
One thousand eight hundred and eighty.