Improved System of Ventilating Sewers, Tunnels, Mines, Buildings, and the like by Induced Currents.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improved System of Ventilating Sewers, Tunnels, Mines, Buildings,
and the like by Induced Currents.
ROBERT GREGORY, 23, Brooksby Street, Islington, London, N., Mechanical
Engineer, do hereby declare the nature of this invention to be as follows:-
The apparatus consists of four or any number of short lengths of tube, forming
annular rings, the first section to commence from a small diameter and the other
sections to increase in diameter to nearly the internal diameter of the shaft or
air duct in which it is to be fixed. Thus the first section may be 6 inches,
second 9" third 12" fourth 15". The ends of these tubes are then inserted into
each other for a short distance and held in their position by spacing pieces. The
whole number will then somewhat resemble a telescope when extended. Fixed
into the centre of the smallest tube is inserted a small pipe with a nozzle at the
end, from which a stream of compressed air or steam, under pressure is made to
issue which drives the foul air before it, and induces the air to flow in and around
the various size tubes, thereby maintaining a continuus current of air to flow
in the direction to that which the apparatus is directed, The tubes may be either
round or square or any shape to suit the shaft or air duct in which it is to be
fixed.
Dated this 24th day of September 1897
Improved System of Ventilating Sewers, Tunnels, Mines, Buildings,
and the like by Induced Currents.
I, ROBERT GREGORY, of 23, Brooksby Street, Islington, London, N., Mechanical
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 an improved system of and means for ventilating by
induced currents such places as railway and other tunnels, sewers, private and
other dwellings, workshops, ships-holds, cabins, and saloons, and other places, for
the purpose of carrying off therefrom vitiated or impure air or gases, and consists
of a series of any number of short lengths of tube or hollow cylinders of different
diameters, the end of the smallest being placed within the end of the next larger
size, and the second size within the next, and so on after the manner of a telescope,
the whole of the said series of tubes or cylinders being retained in connection
Price 8d 1

page_text: with each other and the duct or shaft in which they may be placed by the means
of braces or ties, which also serve as spacing pieces for keeping each length of tube
or cylinder a distance from its neighbour equal to the difference in their respective
diameters, such spaces serving as inlets for the foul or vitiated air or gases drawn
thereinto by induction as hereinafter explained.
Within the smallest section or length of tube or cylinder is placed and fixed
centrally or thereabouts the nozzle of a tube pointing towards the larger sections,
and from this is caused to issue compressed air or steam, which by driving before
it the air in the tubes or cylinders induces the foul or vitiated air or gases to enter
the interstices or annular spaces between, and flow in and around the said tubes,
thereby maintaining a continuous current of air flowing through in the direction
in which the said battery of tubes or cylinders is directed.
In order that my said invention and the manner in which I prefer to construct
and arrange the same may be fully understood, I have hereunto appended a sheet
of drawings in which,
Fig. 1 is a central longitudinal section of a battery of tubes or apparatus accord-
ing to my invention, which will serve to illustrate its principle and general
construction as hereinafter explained.
Fig. 2 is a sectional view of an underground conduit for sewage or other purposes,
and the upcast or ventilating shaft of same, illustrating the application of my
invention in connection therewith.
Fig. 3 is an enlarged sectional view of the smallest of such a battery of tubes,
and the nozzle for injecting steam or compressed air thereinto.
Fig. 4 is an enlarged view of the smallest end of such a battery of tubes, in
which the service of steam or compressed air is divided in two or more injecting
nozzles.
In carrying my invention into effect I construct a battery or cylindrical conduit
composed of any number of short lengths of metallic, earthenware, brick-or-stone-
built, or other tubes, according to their intended uses, and each of a cross-sectional
diameter differing from that of the remainder. In the accompanying drawings
I have chosen to assume that five such pieces of tube or cylinders are employed
in the construction of the said apparatus, but a greater or lesser number may be
employed according to circumstances, and which may or may not be all of the
same length, and of the said five pieces the end of the smallest A I insert for a
suitable distance within one end of the next larger tube B, and the opposite end
of the latter for a like distance within one end of the next C, and so on with
regards to D and E, the whole being brought into fixed connection with
each other by the means of metallic or other stays F, rivetted or otherwise con-
nected thereto, in such a manner, that these also form spacing pieces for providing
an annular space between the end of either tube and the next to which it is
attached.
In Fig. 2 I illustrate the application of my invention for the purpose of ventilat-
ing sewers and other like underground conduits G, in which it is assumed that
such conduits are man-high or thereabouts, and that at certain intervals in their
length the said sewers or other conduits have suitable upcast or other exhausts
such as H for the escape of the foul air or gases generated therein. In such cases
the said battery of tubes may be placed centrally of the diameter of the conduits G,
or near to the roof thereof, or otherwise, and in such a manner that the larger
section E is nearest to the said exhaust or outlet H, the end or other or all the
said sections being retained in their desired position by the means of ties, stays,
or braces such as J (Fig. 1).
For the purposes of my invention I fix within the section A, and pointing in the
direction of E, the nozzle d of a pipe or tube K, adapted to convey from any dis-
tance air or steam under pressure, and the force of such air or steam entering A,
would cause a forced draught through the whole battery of tubes into the said
exhaust H, in the direction of the arrows a, and by reason of such forced draught
being derived from air or vapour under pressure the expansion of this as it exudes

page_text: from each smaller into the next larger section (as indicated by the arrows c) the
noxious or impure air, gases, or vapours in the conduit G would by induction, be
caused to enter the interstices between the sections (as indicated by the arrows b
in Figs. 1, 2 and 3, and be carried direct into the upcast shaft or other exhaust H,
and such current of compressed air or steam may be derived from any convenient
or available source, and may be continuous or at predetermined intervals
desired.
as
In certain cases or where space and other considerations may not permit the
use of so many as five sections in a battery, I may find it convenient for the purpose
of increasing the volume of compressed air or steam entering into and issuing from
the smallest of the tubes employed, say B, to arrange the compressed air or steam
conduit K with two or more, say four, nozzles d, each of which may be within a
tube retained by the means of ties or stays such as J within the smallest tube B
as shewn at Fig. 4.
e,
A battery of tubes constructed as hereinbefore described, but may be having a
larger number of sections, may be employed for ventilating railway and other
tunnels in which case any number of such batteries may be erected in one tunnel
if needed, not necessarily all pointing in the same direction, but all placed prefer-
ably in the highest part of the tunnel, and each provided with its own conduit K,
and all leading into a, or any number of, suitable upcast or exhaust shafts, for
carrying off the impure gases of the tunnel as extracted by the said battery or
batteries.
In like manner a battery of tubes may be erected in any suitable way in ships cabins,
berths, and saloons, for carrying off the vitiated air therein, for which purpose
such a battery may be erected in or near any one or all of the usual ventilating
shafts, and be operated by compressed air generated from the engine room, or for
the purpose of imparting perfect ventilation and other effects to cargo in ships
holds, I may arrange that one or more such batteries of tubes may be employed
for carrying off impure air, while by inverting one or more of the said batteries
in another or other part or parts of the hold, so that the smallest section
sections A thereof, are nearest to the atmosphere, the latter arrangement may be
employed for forcing a current of fresh air into the hold to assist in the eviction
of the impure air or the latter arrangement may be so contrived as to be operated
by air or steam, the latter of which may be usefully employed in case of fire.
or
In large factories or warehouses consisting of several floors, one above the other,
I may ventilate the whole of the said floors by fixing upon the outside of the
building a vertical metallic or other tube or cylinder such as L Fig. 1, of the same
height as the said building, and in which openings may be provided for receiving
the ends of ventilating tubes, one of which may come out from near the ceiling
of each floor and at or near the top of the said tube or cylinder L I fix one of my
said batteries of tubes after the manner illustrated by Fig. 1, in which the ventilat-
ing tube from the top floor of the building is shewn by M, and when such factory,
or warehouse has a steam engine for the purpose of its business, the steam issuing
from the exhaust pipe of the said engine may be conveyed to the conduit K of the
battery for creating the necessary forced draught as hereinbefore explained.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:-
1st. In an improved system of and means for ventilating sewers and other under-
ground conduits, railway and other tunnels, ships-holds, cabins, and saloons, fac-
tories, warehouses and other places, the employment of any number of different sized
metallic or other tubes or cylinders, telescoped and fixed one within the other,
through which is caused. to pass a forced draught derived from air or steam under
pressure, substantially as herein described and shewn.
2nd. In an improved method of and means for ventilating various places, as
set forth in the preceding claim, the combination of a battery, or series of any

page_text: number of tubes or cylinders such as A, B, C, D, and E, telescoped one within the
other, and separated and held together by the means of ties or stays such as F;
the smallest of the said tubes or cylinders receiving one or more nozzles & from a
compressed air or steam conduit K, the whole connected and operating substan-
tially as and for the purposes herein described and shewn by the accompanying
drawings.
CS day of February 1
GEO. THOS. HYDE,
1, Broad Street Buildings, Liverpool Street, E.C.,.
Agent for the Applicant.