Improvements in Signalling and Alarm Apparatus for the Detection of Fire and for other purposes.
Year: 1890

page_text: Date of Application, 13th Jan., 1890
Complete Specification Left, 13th Oct., 1890-Accepted, 22nd Nov.. 1890
PROVISIONAL SPECIFICATION.
Improvements in Signalling and Alarm Apparatus for the Detection
of Fire and for other purposes.
I, WILLIAM EDWARD SMITH, of 33 Bedford Square, Brighton, in the County of
Sussex, Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to pneumatic fire-detectors of the kind or class described in
the Specification accompanying my application for Letters Patent dated 30th May 1889,
No. 9010; and my present invention is designed to improve the construction and
increase the efficiency and utility of the said apparatus.
One object of my present invention is to adapt the apparatus for operating two
distinct and independent signals, one for indicating when a fire occurs, and the other
for calling servants, or for burglar alarms or for indicating when the apparatus is not
in proper working order, or for other purposes. I accomplish this result by so con-
structing the said apparatus that, when charged with air under a pressure greater than
that of the atmosphere, one kind of signal will be given by the compression and
another kind of signal by the rarefaction of the air in the apparatus, acting upon a
flexible diaphragm or upon an expansible chamber.
Instead of using the air-chamber, tube and diaphragm or extensible chamber of the
fire-detector, for the other purposes above-mentioned, I sometimes provide an
independent apparatus comprising a tube which is arranged alongside of the tube of
the fire-detector and which is combined with a flexible diaphragm or an extensible
chamber, and is charged with air under pressure greater than that of the
atmosphere.
Another object of my said invention is to provide for preventing accidental operation
of the apparatus by sudden elevation of the temperature not occasioned by an
outbreak of fire, in a room or other part of a building in which the apparatus is
situated.
My said invention, moreover, comprises an improved air-chamber hereinafter
described. It also comprises the provision of one or more relays or devices for
transmitting the power over long distances, and other improvements as hereinafter
described.
My said invention is conveniently and advantageously carried into practice as
follows, viz. To adapt the fire-detector for indicating whether or not the apparatus
is in proper working order, or for sounding an alarm or giving a signal for calling
servants or for other purposes, I charge the expansible chamber, or the chamber
provided with the flexible diaphragm, and the tube with air under a pressure greater
than atmospheric pressure, so that it will hold in position a plate or disc arranged in
combination with two pivoted arms or levers. One extremity of each of these levers
is provided with a circular or other conveniently shaped indicating label or signal, the
two labels or signals being of different colours, or having distinctive marks to avoid
confusion. These arms or levers are supported by contact or engagement with the
said plate or disc, which rests upon the expansible cushion or chamber. This chaniber
is in communication by means of pneumatic tubes with the several points from which
it is desired that the signals should be transmitted. The said plate or disc is so
arranged in combination with the two pivoted arms or levers that, on being moved in
one direction or raised, it will disengage one of the said arms or levers, while, on being
moved in the reverse direction or lowered, it will disengage the other arm or lever.
The arm thus disengaged falls or turns about its pivot, until it comes in contact with a
stop-piece or plate, in which position the label or signal will be visible through a
suitable aperture or window.
The required movement is imparted to the said plate or disc by expansion or

page_text: contraction of the air in the expansible cushion or chamber, against which the lever is
pressed by a small weight, spring or other suitable device, an adjusting-screw being
provided in connection with the said chamber, whereby its position and consequently
that of the plate or disc supported thereon, can be accurately adjusted.
The expansible chamber or cushion is connected, as described in the said former
Specification, with an air-reservoir, wherein, in case of an outbreak of fire in proximity
thereto, an increase of pressure will occur by reason of the expansion of the air. This
air-chamber I prefer to make in the form of an inverted truncated cone, the inclined
or under surface of which is corrugated so as to increase the extent of heating surface.
In some instances I employ, in combination with the apparatus above described, a
suitable push-piece or other device by the operation of which the air in the apparatus
can be rarefied so as to cause the contraction of the expansible chamber and thus
effect the release of one of the signal-levers. This push-piece or other device may be
arranged in connection with a door, window, drawer or the like, to transmit a signal
on the opening of the same, either by causing a decrease in the pressure of air in the
apparatus. My apparatus is thus very convenient as a burglar-alarm. By arranging
for the opening of a door, window or the like to cause an increase of pressure in the
apparatus, the said apparatus may also be made to serve as a burglar-alarm.
I sometimes use an independent tube, which I solder to the outside of the air-
chamber and carry alongside of the tube of the fire-detector until it reaches the
tell-tale apparatus; here 1 connect it with an independent apparatus wherein the end
of the tube is sealed with a diaphragm which is acted upon in the manner above
described. This is also for detection in case of intentional damage to the air-storage
system, and also for calling servants, or for other purposes.
Moreover I use both the first and second systems above described for burglar-
alarms.
To provide for preventing accidental operation of the apparatus, I sometimes employ
one or more small valves to allow the air within the air-chambers and tubes to escape
when very sudden changes of temperature and consequently of pressure take place
without any outbreak of fire. 1 sometimes use clock-movements for opening and
shutting cocks at certain times, for instance while fires and lights are being kindled in
buildings; I thus prevent or avoid false alarms. I also arrange a pressure-valve
fixed in the tubing just before the tube terminates in the tell-tale apparatus, so that
the action of air in the air chamber does not directly affect the diaphragm in the tell-
tale apparatus, but acts through the medium of this pressure-valve, which regulates
the action of the tell-tale apparatus.
In some cases, I provide suitable means whereby the motion of the aforesaid plate
or disc or the fall of one or other of the pivoted arms or levers will release a weight
or the like, which, acting upon a compressible air-chamber, will increase the pressure
therein and will thereby act as a relay for ringing a bell or for transmitting a signal
over a second length of tube.
It is obvious that my said invention may be modified in certain details without
departing from the nature thereof.
Dated this 13th day of January 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Signalling and Alarm Apparatus for the Detection
of Fire and for other purposes.
WILLIAM EDWARD SMITH, of 33 Bedford Square, Brighton in the County of
Sussex, 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 :—
My invention relates to pneumatic fire-detectors of the kind or class described
in the Specification accompanying former Letters Patent granted to me dated

page_text: 30th May A.D. 1889 No. 9010; and is designed to improve the construction and
increase the efficiency and utility of the said apparatus.
One object of my present invention is to adapt the apparatus for operating two
distinct and independent signals, one for indicating when the fire occurs, and the other
for calling servants or for burglar alarms, or for indicating when the apparatus is not
in proper working order or for other purposes. I accomplish this result by so con-
structing the apparatus that when charged with air under a pressure greater than that
of the atmosphere, one kind of signal will be given by the compression, and another
kind of signal by the rarefaction of the air in the apparatus acting upon a flexible
diaphragm or upon an expansible cushion or chamber.
Instead of using the air-chamber, tube and diaphragm or extensible or expansible
cushion or chamber of the fire detector for the other purposes above mentioned, I
sometimes provide an independent apparatus comprising a tube which is arranged
alongside of the tube of the fire-detector and which is combined with a flexible diaphragm
or an extensible or expansible cushion or chamber, and is charged with air under
pressure greater than that of the atmosphere.
Another object of my said invention is to provide for preventing accidental operation
of the apparatus by sudden elevation of the temperature not occasioned by an
outbreak of fire, in a room or other part of a building in which the apparatus is
situated.
My said invention moreover, comprises an improved air-chamber hereinafter
described.
It also comprises the provision of an improved relay or device for transmitting
the power over long distances and other improvements as hereinafter described.
In the accompanying drawing I have shown how my said invention may be con-
veniently and advantageously carried into practice.
Figure 1 is a front elevation a portion of the box or case being removed showing
an indicator or tell-tale apparatus for operating two distinct and independent signals
constructed according to my present invention.
Figure 2 is a similar view to Figure 1 showing an arrangement wherein I employ
a separate and independent indicator or tell-tale apparatus for operating the second
signal.
Figure 2" is a side elevation in vertical section through the box or casing showing
an improved device for operating the second signal.
Figure 3 is a similar view to Figures 1 and 2 showing an improved relay or
arrangement for transferring or transinitting power.
Figure 4 is a plan, and
Figure 5 is a side elevation showing my improved air chamber.
Like letters indicate corresponding parts throughout the drawing.
A is the box or casing, B is the expansible or extensible cushion or chamber, or
the chamber provided with the flexible diaphragm, B₁ is the pipe leading therefrom to
the air chamber, B2 is the air chamber.
C is a plate, disc, or detent lever one side or extremity of which is hinged or jointed
at C to a bracket D secured to the box or case A. The plate or detent lever C rests
upon the upper side or surface of the expansible cushion or chamber B either directly,
or through the medium of an extension C2 firmly secured to or formed on the said
plate or detent lever C. E, E are arms or levers pivoted at E to the said box or
case A. The arm or lever E is provided at iis upper or one extremity with a circular
or other conveniently shaped label or signal F, and the arm or lever E' is provided
at its upper or one extremity with a circular or other conveniently shaped label or
signal F. The labels or signals F F are preferably of different colours, or have
listinctive marks thereon to prevent confusion, and they may also have numerals or other
signs thereon indicative of the room or other place from which the signal originates.
The expansible cushion or chainber B and the tube B' is charged with air under a
pressure greater than atmospheric pressure, so that under normal conditions it will
hold the plate, disc, or detent lever C in such a position as to engage with the extremities
of the pivoted arins or levers E E' and support them in an elevated position as herein-

page_text: after described. That is to say, the lower extremity of the arm or lever E engages
with the edge or free extremity of the plate, or detent lever in such a manner that
should the extensible or expansible cushion or chamber B collapse or sink owing to
the rarefication of the air therein the said plate or lever will fall or move downwards
through a certain angle and release the said extremity of the arm or lever E. The
lower portion of the arm or lever E¹ is bent or curved as shown at E3 or otherwise so
that the extremity thereof extends in an upward direction and engages with an arm
or projection C³ firmly secured to, or formed on the plate or detent lever C, in such a
manner that should the expansible cushion or chamber B rise owing to the expansion
of the air contained therein the said extremity of the arm or lever E' will be released.
The arms or levers E, E' are so set as to be slightly out of the perpendicular and the
said labels or signals F F¹ form counterbalance weights for ensuring the descent of
the said arms or levers E E¹ when tripped or released and for operating the signal-
bell or alarm-bell as hereinafter described. The extension C2 moreover forms a weight
which ensures the descent of the plate or detent lever Ċ when the said expansible
cushion or chamber B sinks or collapses. F is a thumb-screw arranged to screw into
a correspondingly screw threaded nut or socket G secured in the box or case A, and
provided at one extremity with a suitable milled head F' and at the cther with a plate
or disc F2 adapted to bear against and support the underside of the expansible cushion
or chamber B. H is a lever pivoted at H to the box or case A. I is a compressible
air chamber which is supported by a bracket I¹ secured to the box or case A; and
communicates with the signal-bell or alarm-bell through a pipe or tube 12. The free
extremity of the said lever H is supported upon the flexible upper surface of the said
compressible air chamber I and is provided with a cross piece or plate H2 against
which one or other of the signals or labels F F will strike when the corresponding
arm or lever is tripped or released from the plate or detent lever C. and turns about
its pivot (as shown in dotted lines in the drawing), thereby compressing the air in the
compressible air chamber I so as to set the signal-bell or alarm-bell ringing. When
in this position the said label or signal will be visible through a suitable aperture or
window in the box or case A. B is a branch pipe and B is a stop cock or valve by means
of which the compressed air in the tube B and collapsible cushion, or chamber B
can be permitted to escape so as to regulate or adjust the said pressure as desired.
The expansible cushion or chamber B is in communication by means of the
pneumatic tube B¹ with the point from which it is desired that the signal should
be transmitted.
The required movement is imparted as hereinbefore mentioned to the said plate
disc or detent lever C by expansion or contraction of the air in the expansible cushion
or chamber. B, and the position of the said expansible cushion or chamber and con-
sequently that of the plate, disc, or lever supported thereon relatively to the pivoted
levers E E¹, can be accurately adjusted by means of the thumb-screw F.
The extremity of the pneumatic pipe B₁ remote from the expansible chamber or
cushion B is connected as described in the said former Specification with an air-
reservoir wherein, in case of an outbreak of fire in proximity thereto an increase of
pressure will occur by reason of the expansion of the air. This air-chamber I prefer
to make in the form of an inverted truncated cone, B² (Figures 4 and 5) the inclined
or under surface of which is provided with corrugations B* so as to increase the extent
of heating-surface. The increased pressure caused by the expansion of the air will
also expand the said expansible cushion or chamber B raise the plate disc, or detent
lever C, and release the arm or lever E¹ and label or signal F¹ as hereinbefore
described
In order to effect the contraction of the expansible cushion or chamber B and
thereby permit the descent of the plate or detent lever and release the arm or
lever E, and signal or label F, for calling a servant or the like the air in the
expansible or extensible cushion or chamber B is rarefied. To permit this rarefication
of the air to be effected when desired without allowing any of the said air to escape,
or permanently reducing the pressure in the pneumatic tube B', and expansible
cushion or chamber B, I provide at the point from whence the signal is to be

page_text: dispatched a device (shown in Figure 2ª) somewhat similar in appearance outwardly
to the knob or push-piece usually employed in connection with pneumatic bells.
a is the box or casing in which is arranged a cushion or bellows b. c is a handle
or stem mounted in the said box or casing a one extremity of which is provided with
a knob c and the other extremity of which is secured to the free or movable
extremity or portion of the said cushion or bellows. d is a spiral or other spring for
retaining the said cushion or bellows collapsed or compressed. e is a pin or stop
provided upon the stem c and adapted to bear against the box or case a, or against a
socket a provided thereon so as to prevent excessive compression of the cushion or
bellows b under the action of the spring d. f is a pipe one extremity of which is
connected with the said cushion or bellows d and the other extremity of which is
intended to be connected with the pipe or tube B¹. It will be seen that by pulling
or drawing out the stem or handle c so as to compress the spring d, the bellows
will be distended or expanded (as shown in dotted lines in Figure 2") and the air
under pressure in the expansible cushion or chamber B and pipe or tube B¹ will be
rarefied so as to reduce the pressure and permit the contraction of the said expansible
cushion or chamber B and effect the release of the arm or lever E and signal or
label F as hereinbefore mentioned. Instead of the cushion or bellows 61 sometimes
so arrange the said knob or push piece c that when out of operation it acts to retain
a flexible metallic or other diaphragm, arranged in the box or case a, or in the
pneumatic pipe or tube B¹, or in a pipe or tube connected therewith, distended or
expanded inwardly thereby maintaining the required pressure in the tube B¹, and
expansible cushion or chamber B. When the knob or push-piece however is operated
to give the signal, the said flexible metallic or other diaphragm or cushion is
permitted to collapse and the air in the said tube B₁ and expansible cushion or
chamber B is rarefied.
An apparatus constructed as hereinhefore described forms a duplex or compound
indicator or tell-tale by means of which two signals can be given without danger of
mistakes. The said apparatus moreover forms a safety device as should a leakage
occur in any portion of the expansible cushion or chamber B or tube B¹, either
through accident or from wilful damage thereto the air will escape, and the pressure
therein will consequently decrease or fall to the ordinary atmospheric pressure, and the
arm or lever E and signal or label F be released as before stated.
In some instances 1 employ the apparatus as a burglar alarm. For this purpose
I so arrange the hereinbefore mentioned push piece or other device in connection
with a door, window, drawer or the like as to transmit a signal on the opening of the
same by causing a decrease in the pressure of air in the apparatus. I sometimes
arrange for the opening of a door, window drawer or the like to transmit a signal
by causing an increase of pressure of air in the apparatus.
I sometimes use an independent tube which I solder to the outside of the air-
chamber and carry alongside of the tube of the fire-detector until it reaches the
indicator or tell-tale apparatus here I connect it with an independent apparatus such
as shown in Figure 2. In this case the arm or lever E' and signal or label F¹ is
dispensed with, one arm or lever E and signal or label F only being employed. The
signal or label F is sometimes constructed in the form of a square parallelogram or
the like. E is an adjustable counterweight for counterbalancing the signal or
label F, and preventing it from descending with too much force upon the compres
sible cushion or air chamber I. This arrangement is operated by a rarefication of
the air in the tube B' and collapsible cushion or chamber B in a manner
substantially similar to that herein before described, and is likewise available for the
detection of intentional or accidental damage to the air-storage system, and also for
calling servants, and for a burglar alarm, or for other purposes.
To provide for preventing accidental operation of the apparatus I sometimes
employ one or more small valves to allow the air within the air chambers and tubes
to escape when very sudden changes of temperature and consequently of pressure take
place without any outbreak of fire. I sometimes use clock movements for opening
and shutting cocks at certain times for instance while fires and lights are being

page_text: kindled in buildings, I thus prevent or avoid false alarms. I also sometimes arrange
a pressure valve fixed in the tubing just before the tube terminates in the indicator
or tell-tale apparatus so that the air pressure in the air-chamber does not directly
affect the diaphragm in the tell-tale apparatus but acts through the medium of this
pressure valve which thus regulates the action of the tell-tale apparatus.
Figure 3 illustrates an improved relay or arrangement for transferring power.
J is an arm or lever hinged or jointed at J¹ to the box or case A. J2 is a weight
firmly secured to or formed on the upper or free extremity of the said arm or lever J.
K is a thumb screw provided with a milled or other head K' and adapted to screw
into a nut or socket L firmly secured to the box or case A. The arm or lever J is
so arranged as to rest (when out of operation) against the expansible chamber or
cushion B and thumb-screw K at a slight inclination from the perpendicular. When
the said arm or lever J is moved past its centre of gravity in the other direction by
the expansion of the expansible cushion or chamber B it turns upon the hinge or
joint J and the weight J2 striking against the compressible air-chamber 1 increases
the pressure of the air therein and either acts as a relay for ringing the alarm or
signal-bell, or for transmitting or transferring a signal over a second length of tube.
The thumb-screw K forms a stop against which the arm or lever J bears as before
stated when in its elevated position and by means of which it is prevented from resting
so heavily against the expansible, cushion or chamber B as to interfere in any way
with the free operation thereof. The said arm or lever moreover can be adjusted by
means of the said thumb-screw towards or away from the vertical position thereby
rendering it more or less difficult, or requiring more or less expansion of the
expansible cushion or chamber B to cause it to turn upon the hinge or joint J¹.
I sometimes employ the above described arrangement as an indicator or tell-tale.
It is obvious that my said invention may be modified in certain details without
departing from the nature thereof.
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. In or for a fire-detector of the kind or class hereinbefore mentioned an
indicator or tell-tale having an air storage in which the pressure is slightly above that
of the atmosphere, and so arranged that a predetermined increase of the said pressure
or condensation of the air therein, will operate to release one signal or label, and a
predetermined decrease of the said pressure or rarefication of the said air will
operate to release another signal or label, substantially as and for the purposes set forth.
Second. An indicator or tell-tale comprising an expansible cushion or chamber, a
hinged or jointed plate, or detent lever supported thereby, and so arranged in
combination with two label or signal arms or levers that a predetermined movement
thereof in one direction will release one of the said arms or levers, and a predeter-
mined movement thereof in the other direction will release the other arm or lever,
substantially as described.
Third. The push-piece and flexible diaphragm for enabling the rarefication of the
air in the air storage to be effected when desired, substantially as described.
Fourth. The improved air-chamber constructed in the form of an inverted
truncated cone, and the inclined, or underside or surface whereof is suitably corrugated
substantially as, and for the purpose specified.
Fifth. The arrangements for preventing the accidental operation of the apparatus
through very sudden changes of temperature other than that caused by an outbreak
of fire, comprising either suitable relief valves, cocks operated by clock movements,
or a pressure valve arranged in the air storage, or a combination thereof, substantially
as described.
Sixth. The modification substantially as described with reference to Figure 2 of
the accompanying drawing.
Seventh. The improved relay or device for transferring or transmitting power
substantially as described with reference to Figure 3 of the accompanying drawing.

page_text: Eighth. The improved apparatus constructed substantially as described with
reference to Figure 1 of the accompanying drawing and operating as and for the
purpose herein before specified.
Dated this 4th dow of Arisham 1800
WILLIAM EDWARD SMITH.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.