IMPROVED PNEUMATIC SIGNALLING APPARATUS FOR USE IN BUILDINGS."
Year: 1874

page_text: LETTERS PATENT to John Farrand Clarke, of Moorgate Street, in the
City of London, for the Invention of "IMPROVED PNEUMATIC SIGNALLING
APPARATUS FOR USE IN BUILDINGS."
PROVISIONAL SPECIFICATION left by the said John Farrand Clarko
at the Office of the Commissioners of Patents, with his Petition,
on the 27th March 1874.
I, JOHN FARRAND CLARKE, of Moorgate Street, in the City of
London, do hereby declare the nature of the said Invention for "Iм-
PROVED PNEUMATIC SIGNALLING APPARATUS FOR USE IN BUILDINGS,” to be as
follows:-
My Invention relates to improved pneumatic signalling apparatus for
summoning attendants in private and public buildings, and such like
purposes.
:
The apparatus is adapted to give an audible and visible signal by
sounding a bell and exhibiting a plate bearing a number or other sign
to denote the source whence the signal émanatės,

page_text: In such apparatus as hitherto constructed it has been necessary after
giving a signal that the attendant should put back the plate out of sight,
and by the same movement wind up the bell-striking mechanism. Owing
however to the neglect of the attendant in allowing the plates to remain
exhibited after answering the signal confusion and inconvenience have
arisen, inasmuch as after a few signals the source of that last given has
been uncertain owing to several different plates being allowed to remain
visible at the same time. Moreover as the bell fails to sound in con-
sequence of not being wound up the apparatus is unreliable and becomes
almost entirely useless.
Now my Invention has for its object to dispense entirely with the
resetting of the apparatus, so that it shall not be disabled by the neglect
of the attendant in. this particular, or require any other attention what-
ever.
The indicating apparatus comprises a case having apertures at which
plates or hinged flaps are exhibited (numbered to indicate the room to
which they correspond) through the.agency of an elastic ball, diaphragm,
or disc covering a cup or cone, and provided with a push piece as usual;
from which an air tube leads to the apparatus, said tube terminating
in an air-tight expansible chamber; by the movement of which the
numbered plate is brought opposite its aperture. When any one of the
said plates is exhibited at its aperture it is retained in that position by a
latch until another signal is given and another plate exhibited, where-
upon the first plate is removed or allowed to fall. This is effected through
the agency of the following mechanism:-At the same time that any.
one of the plates is exhibited, the movement of its air chamber is caused
to oscillate a rock shaft common to all, which shaft carries arms which
abut against a rod, whereby all the latches ar disengaged. Should
however two.plates be exhibited at one time by signals given simul
taneously from two different sources they will both remain visible until
a third one is exhibited. A lever arm on the same rock shaft actuates
the bell-striking mechanism by moving another lever arm on the axis of
a toothed wheel, which on being partly rotated oscillates the. bell
hammer, provision being made to admit of the lever returning at once
to its normal position after the bell has been sounded, so as to allow of.
a second signal being given immediately afterwards if desired.
In some cases it may however be desirable that the plates or flaps
should remain exhibited until removed by the attendant, in which case I

page_text: should provide a push rod connected to the rod by which the latches,
are released, to be moved by the attendant, and so arranged as to wind.
as usual the clock motion, which would in this case be used for striking.
the bell.
Instead of exhibiting a plate or flap at an opening, the expansion of
the air chamber may be made to swing a pendulum by raising a corre-.
sponding arm, the end of which takes under a short lever or dog
abutting against the pendulum. .
The several pendulums are actuated by independent air chambers on 1
pipes communicating with the different rooms, the pendulums being,
distinguished by signs or words. as in former cases.
4
The movement of the air chamber also oscillates the rock shaft, and
causes the bell to be sounded by the agency of mechanism actuated as
before described in the first arrangement.
This striking mechanism may also be used as a repeating bell for com-
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Farrand Clarke in the Great Seal Patent`
Office on the 26th September 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
FARRAND CLARKE, of Moorgate Street, in the City of London, send.
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters"
Patent, bearing date the Twenty-seventh day of March, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,"
give and grant unto me, the said John Farrand Clarke, Her special
license that I, the said John Farrand Clarke, my exccutors, admini-
strators, and assigns, or such others as I, the said John Farrand Clarke,
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,
usc, excrcise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
4

page_text: "IMPROVED PNEUMATIC SIGNALLING APPARATUS FOR USE IN BUILDINGS," upon
the condition (amongst others) that I, the said John Farrand Clarke,
my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and scals, 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 immediately:
after the date of the said Letters Patent. .
NOW KNOW YE, that I, the said John Farrand Clarke, do hereby
declare the nature of the said Invention, and in what manner the same ]
is to be performed, to be particularly described and ascertained in and
by the following statement reference being had to the two accom-
panying Sheets of Drawings, and to the letters and figures marked,
thereon (that is to say) :-
•
My Invention relates to improved pneumatic signalling apparatus for 1
summoning attendants in private and public buildings and such like
purposes.
The apparatus is adapted to give an audible and visible signal by
sounding a bell and exhibiting a plate bearing a number or other sign
to denote the place from whence the signal emanates.
In such apparatus as hitherto constructed it has been necessary after
giving a signal that the attendant should put back the plate out of sight,
and by the same movement wind up the bell-striking mechanism. Owing
however to the neglect of the attendant in allowing the plates to remain,
exhibited after answering the signal, confusion and inconvenience have
arisen, inasmuch as after a few signals the place from whence the last
was given has been uncertain, owing to several different plates being
allowed to remain visible at the same time. Morcover, as the bell fails
to sound in consequence of the mechanism not being wound up, the
apparatus is unreliable and becomes entirely useless.
Now my Invention has for its object to dispense entirely with the.
resetting of the apparatus, so that it shall not be disabled by the neglect,
of the attendant.
The indicating apparatus comprises a case having apertures at which
plates or hinged flaps numbered to indicate the room to which they a
correspond, are caused to be exhibited through the agency of an elastic-

page_text: -
ball, or a disc covering, a cup or cone, and provided with a push picce
as usual, from which an air tube leads to the indicating apparatus, said
tube terminating in an air-tight expansible chamber, by the movement
of which the numbered plate is brought opposite its aperture. When,
any one of the said plates is exhibited at its aperture, it is retained in
that position by a latch until another signal is given, and another plate.
exhibited, whereupon the first plate is allowed to fall. This is effected.
by the agency of the following mechanism :-At the same time that any.
one of the plates is exhibited, the movement of its air chamber is caused
to oscillate a rock shaft, carrying arms which abut against a rod, whereby
all the latches are disengaged. Should however two plates be exhibited
at one time by signals given simultaneously from two different places,
they will both remain visible until a third one is exhibited. A lever.
arm on the same rock shaft actuates the bell-striking mechanism by.
3. moving another lever arm on the axis of a toothed wheel, which on
being partly rotated oscillates the bell hammer, provision being made to.
admit of the lever returning at once to its normal position after the bell-
has been sounded, so as to allow of a second signal being given imme..
diately afterwards if desired.
)
"
Instead of exhibiting a plate or flap at an opening the expansion of
the air chamber may be made to swing a pendulum by raising a corre.
sponding arm, the end of which takes under a short lever abutting
against the pendulum.
The several pendulums are actuated by independent air chambers or
pipes communicating with the different rooms, the pendulums being
distinguished by signs or words as in former cases.
'
The movement of the air chamber also oscillates the rock shaft and
causes the bell to be sounded by the agency of mechanism actuated as
before described in the first arrangement.
This striking mochanism may also be used as a repeating bell for
communicating from one place to another or other purposes.
DESCRIPTION OF DRAWINGS.
Figure 1 is an elevation of the front of the case containing the
indicator.
Ticum 2 is on alavati

page_text: In this case the lever p is oscillated by a rod x jointed thereto, resting
directly upon the air chamber e.
Having described the nature of my Invention and the manner of per-
forming the same, I declare that what I claim as the Invention to be
protected by the herein-before in part recited Letters Patent is,—
1st. The employment in combination with the hinged number plates c
of the latches 1, so arranged and operated that on the rising of any one
of the air chambers e, all the latches will be released, as and for the
purpose specified.
2ndly. The combination with each air chamber e of a hinged plate ƒ
for raising the number plate c, and supporting it by the projection c¹
until its latch 2 drops and retains it, substantially as shown and
described.
3rdly. The combination with the series of air chambers e of the rock
shaft, having arms k and n, the latter taking under a rod m for
releasing all the catches / at once, substantially as shown and described.
4thly. In combination with each air chamber e a hinged plate fter-
minating in a finger f¹ working through a slot and acting on a pen-
dulum through the intervention of a lever u and arm v, substantially as
described.
5thly. The mechanism for sounding the bell, constructed and operating
substantially as shown and described, whether actuated by an arm from
the indicator or directly by an expansible air chamber, as and for the
purpose set forth.
In witness whereof I, the said John Farrand Clarke, have to this
my Specification set my hand and seal, this Twenty-third day
of September, in the year of our Lord One thousand eight
hundred and seventy-four.
J. F. CLARKE. (L.S.)