IMPROVEMENTS IN SAFETY ALARM SIGNALLING APPARATUS TO BE USED IN CONNECTION WITH STEAM BOILERS
Year: 1879

page_text: LETTERS PATENT to William White, of Greenock, in the County of Renfrew,
North Britain, Brass Founder and Bell Hanger, for the Invention of
"IMPROVEMENTS IN SAFETY ALARM SIGNALLING APPARATUS TO BE USED IN
CONNECTION WITH STEAM BOILERS."
Sealed the 27th February 1880, and dated the 17th December 1879.
Sealed the 27th February 1880, and dated the 17th December 1879.
PROVISIONAL SPECIFICATION left by the said William White at the Office
of the Commissioners of Patents on the 17th December 1879.
WILLIAM WHITE, of Greenock, in the County of Renfrew, North Britain, Brass
Founder and Bell Hanger. "IMPROVEMENTS IN SAFETY ALARM SIGNALLING
APPARATUS TO BE USED IN CONNECTION WITH STEAM BOILERS."
This Invention relates to a new or improved construction or arrangement of
electric signalling apparatus to be used in connection with steam boilers for giving
an alarm or warning when the pressure of steam in the boiler, as indicated by
the
gauge to which the apparatus is fitted, reaches to or rises beyond the maximum
at which the boiler is intended to be worked; and the improved apparatus is also
designed for giving a similar aların, when the water within the boiler is con-
siderably higher or lower than the normal position.
By one arrangement of the improved apparatus as applied to the pressure gauges
of steam boilers, in addition to the usual indicating hand or pointer moving round
the dial face of the gauge, and marking the pressure of the steam in the boiler,
there is fitted a stationary hand which may be moved round and set at a point
indicating any desired degree of pressure on a swivelling pivot, centre pin, or stud
fitted in a small metallic bracket secured over the face of the gauge to the metallic
bezel ring holding the usual glass face, but separated or insulated by that ring by
a wooden, vulcanite, or other non-conducting piece interposed between the metallic
portion of the bracket and the ring, and this fixed or stationary hand or pointer
is provided with an inner projecting pin or stud with which the moving indicating
hand or pointer comes into metallic contact, when by the boiler pressure it is
caused to travel round the gauge to indicate the pressure at which the stationary
hand is set. The usual moving hand or pointer is connected by metallic contact of
the parts of the gauge with a wire held by a binding screw in contact with the

page_text: gauge, and leading to one pole or an electrode of an electric battery, and the insulated
setting hand or pointer is also connected by an insulated wire passing round and
out of the gauge to a second binding screw fitted close to the first, and to which a
wire is attached leading through the magnet coil of an ordinary electric trembling
bell to the other pole or electrode of the battery.
And when the pressure of the steam in the boiler causes the moving hand to
travel round to and make contact with the projecting pin on the setting pointer or
hand, the electric circuit is completed through the wires, and the pointers of the
gauge causing the bell to ring and warn the fireman or attendant until the pressure
of steam is again reduced.
The bezel ring holding the glass over the face of the gauge may be hinged or
otherwise fitted to it and securely locked, after the stationary hand or pointer is
set at the number expressing the limit of pressure to which it is desirable or safe
to work the boiler, so that this hand may not be re-set or tampered with by the
fireman or other attendant; but in cases where the maximum of pressure to which
the boiler is worked would be constant, or never exceed a given amount, an
insulated terminal plate might be fitted to the metallic bezel ring of the gauge
with which the moving hand or pointer would come in contact when it reached
to and indicated the limiting pressure, and would then cause the electric bell to
ring or give an alarm.
In another application of the improved apparatus intended to give an alarm or
warning of the water in a boiler, either rising considerably above or falling below
the normal position, the usual rod or lever passing from an indicating float in the
boiler is fitted with a small pointer or lever and is connected by a wire to an
electric battery. When the float would rise or fall with the water in the boiler
considerably above or below its usual level this pointer would correspondingly rise
or fall, and come into metallic contact with an upper or lower contact spring on a
stationary insulated terminal plate, connected by a wire leading through the
magnet coil of a trembling bell to the battery and would cause the bell to sound an
alarm.
In both these arrangements of safety alarm signalling apparatus described the
electric bell might be fitted in the engine room, and an additional electric bell
acted on by the same battery and set of wires might also be placed in the magager's
or engineer's room, and in works where a large number of boilers are used the
improved apparatus might be connected to the gauges and water level indicator of
each boiler and only a single bell used in the engine room or manager's office, but
the wires fitted to each separate gauge or indicator would pass through a separate
magnet coil for each boiler, which would cause a semaphore or other visible signal
fitted in connection with each magnet, to be exhibited or displayed to the manager
at the same time as the bell would ring, for the purpose of indicating at which
boiler of a set or series the pressure or water level was beyond the normal point.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William White in the Great Seal Patent Office on the 16th June
1880.
WILLIAM WHITE, of Greenock, in the County of Renfrew, North Britain, Brass
Founder and Bell Hanger. " IMPROVEMENTS IN SAFETY ALARM SIGNALLING
APPARATUS TO BE USED IN CONNECTION WITH STEAM BOILERS."
My said Invention relates to a new or improved construction or arrangement of
electric signalling apparatus, to be used in connection with steam boilers, for giving
an alarm or warning when the pressure of steam in the boiler, as indicated by the
gauge to which the apparatus is fitted, reaches to or rises beyond the maximum at
which the boiler is intended to be worked; and the improved apparatus is also
designed for giving a similar alarm when the water within the boiler is considerably
higher or lower than the normal position.
And in order that my said Invention, and the manner in which the same is to be
performed or put into effect or practice may be properly understood, I have here-
unto appended a Sheet of explanatory Drawings for that purpose, representing
modifications of my improved alarm-signalling apparatus which I shall now proceed
to describe. In these Drawings the same reference letters are used to indicate the
same or like parts where they are shown.
Referring to the Drawings, Figure 1 is a front elevation, and Figure 2 is a vertical
section at right angles thereto, of a modification of my improved electric signalling
steam pressure gauge; Figures 3 and 4, are longitudinal vertical sections of steam
boilers fitted with my improved electric-alarm signalling apparatus, and Figure 5
is an end elevation showing several boilers with my improved electric apparatus.
In the arrangement of my improved apparatus as applied to the pressure gauge A
of a steam boiler, in addition to the usual indicating hand or pointer A', moving
round the dial face of the gauge, and marking the pressure of the steam in the
boiler, there is fitted a stationary pointer B, which may be moved round by hand,
and set at a point indicating any desired degree of pressure on a swivelling pivot,
centre-pin, or stub B', fitted in an oye in a small metallic bracket or rod C, secured
over the face of the gauge A to the metallic caso A", or bezel ring holding the usual
glass face, but separated or insulated from that case or ring A" by a wooden,
vulcanite, or other non-conducting piece C interposed between the metallic portion
of the bracket or rod C, and the ring or caso A". This fixed or stationary hand or
pointer B is fitted with a tip of platinum soldered on at b, or provided with an inner
projecting pin or stud with which the moving indicating hand or pointer A², or a
curved platinum wire a thereon, comes into metallic contact, when by the boiler
pressure it is caused to travel round the gauge A, to indicate the pressure at which
the stationary hand B is set, that is, in the example shown, 50 lbs. pressure. The
insulated setting hand or pointer B is connected by an insulated wire or rod c,
passing out of the gauge A through the insulator Č¹, with a wire A+, held by a
binding screw c¹ in contact with the gauge, and leading to one pole or electrode of
an electric battery D, and the usual moving hand or pointer A³ is also connected by
a wire A- attached to the case A", and leading from the gauge A through the
magnet coil of an ordinary electric trembling bell E to the other pole or electrode
of the battery.
When the pressure of the steam in the boiler causes the moving hand to travel
round to and make contact with the projecting pin or platinum tip b, on the setting
pointer or band B, the electric circuit is completed through the wires A+, A-, and
the pointers A, B, of the gauge cause the bell E to ring and warn the fireman or
attendant, until the pressure of steam is again reduced.
The bezel ring holding the glass over the face of the gauge, is hinged at A³, or it
maw be otherwise fitted to it, and securely locked by means of a pad-lock fitted

page_text: at A³, after the stationary band or pointer B is set at the number expressing the
limit of pressure to which it is desirable or safe to work the boiler, so that this
hand may not be reset or tampered with by the fireman or other attendant. In
cases where the maximum of pressure to which the boiler is worked would be
constant, or never exceed a given amount, an insulated terminal plate might be
fitted to the metallic bezel ring of the gauge, with which the moving hand or
pointer would come in contact when it reached to and indicated the limiting
pressure, and would then cause the electric bell to ring or give an alarm. The
apparatus may also be made to sound an alarm when the boiler pressure, as indicated
by the gauge, becomes lower than is desirable, by fitting an additional insulated
hand on the rod C, which would be set at the minimum working pressure by hand
after steam is raised in the boiler, and the moving hand indicates a higher
pressure. The same arrangement of apparatus is obviously applicable to vacuum
gauges.
In the application of the improved apparatus shown in Figure 3, which is intended
to give an alarm or warning of the water in a boiler Z, either rising considerably
above, or falling below the normal position, the usual rod or lever A¹ passing from
an indicating float F in the boiler, is fitted with small pointers or levers a, and is
connected by metallic contact of the parts of the boiler to a wire A- attached to
the boiler Z, and leading to an electric battery.
b
When the float F rises or falls with the water in the boiler, considerably above
or below its usual level, these pointers a, correspondingly rise or fall, and come into
metallic contact with a platinum contact point 6 on a stationary insulated terminal
plate B connected by a wire A+ leading through the magnet coil of a trembling
bell to the battery, and causes the bell to sound an alarm to indicate such unusual
rise or fall of the water level.
By a slight modification of this alarm apparatus shown in Figure 4, the float F
is connected by a cord or chain with a balance weight passed over a pulley G,
carried on a spindle in the bracket G', over the boiler Z. The spindle of the pulley G
is fitted with a hand or pointer A', which moves with the pulley as it oscillates or
revolves by the action of the float and weighted cord, and when this pointer A¹
moves considerably round to one side or other to indicate in the usual manner an
extreme rise or fall of the water in the boiler, this pointer comes into metallic
contact with a stationary pin or stud B of platinum or other metal on either side of
the usual indicating segment B¹, which is in this case however insulated from the
bracket G. The insulated segment B and bracket G¹ are fitted with wires A+, A—,
leading to a battery and bell coil, and the making of contact between the pointer A¹
and stud B, causes an alarm to be sounded and indicate audibly that the water level
is extremely high or low.
In these arrangements of safety alarm signalling apparatus described, the electric
bell might be fitted in the engine room, and an additional electric bell acted on by
the same battery and set of wires might also be placed in the manager's or
engineer's room. In works where a large number of boilers are used, the improved
apparatus can be connected to the gauges or water level indicators of each boiler,
and only a single bell used in the engine room or manager's office.
Figure 5 shows an arrangement of this latter kind applied to the gauges of a set
of three boilers Z. The gauges A are of the construction described in reference to
Figures 1 and 2, and their insulated hands B are fitted with wires A+ leading to
a battery D, while the gauge cases are directly connected by wires A- to an
electric bell apparatus E, fitted with as many semaphores as there are gauges A.
The wires A-, fitted to each separate gauge or indicator H, pass through a separato
magnet coil which causes its semaphore, or it might be any other visible signal
fitted in connection with its magnet, to be exhibited or displayed through the
openings e on the face of the bell box E in the manager's or engineer's office at the
same time as the bell rings, for the purpose of indicating at which boiler of a set
or series the pressure or water level is beyond the normal point.
Having thus particularly described my said Invention, and the manner in which

page_text: the same is to be performed, I have to state that I do not restrict myself to
the precise details lierein described or delineated, but what I believe to be novel
and original, and therefore claim as the Invention socured to me by the hereinbefore
in part recited Letters Patent is,―
First. The construction of a pressure or vacuum gauge for steam boilers having
an insulated stationary or setting hand or pointer B, with which the ordinary
moving hand makes contact, and completes an electric circuit through wires A+,A-,
connected to a battery and electric bell, so as to sound an alarm when the boiler
pressure is above or below the desired working limit, all substantially as herein
described with reference to and shown in Figures 1 and 2 of the accompanying
Drawings.
Second. The construction and use of a water float F in a steam boiler, in
connection with a rod A' or pulley and indicator B', and bracket B, fitted with
wires leading to a battery and electric alarm bell, through which an electric circuit
is completed by metallic contact of the parts when the water level is raised or
lowered beyond the desired limit, all substantially as and for the purposes herein
described in reference to Figures 3 and 4 of the accompanying Drawings.
Third The general arrangement of electric apparatus shown in Figure 5, in
connection with the gauges or water level indicators of a set of steam boilers, for
the purpose of indicating an alarm bell and semaphores or signals in a manager's
office, or distant station, when one or more of the boilers is worked beyond the
desired limits of pressure or water level, all substantially as herein described.
In witness whereof, I, the said William White, have hereunto set my hand
and seal, this Eighth day of June, in the year of our Lord One thousand eight
hundred and eighty.
Witness,
WALLACE FAIRWEATHER, C.E.,
of W. R. M. Thomson & Co.,
Patent Agents,
Glasgow.
WILLIAN WHITE. (L.S.)