Improvements in Ventilation and in Distribution of Warmth by Movements of Air.
Year: 1891

page_text: Date of Application, 16th Apr., 1891
Complete Specification Left, 15th Feb., 1892-Accepted, 2nd Apr., 1992
PROVISIONAL DEPUITIATIVAR
Improvements in Ventilation and in Distribution of Warmth by
Movements of Air.
I, JAMES THOMSON, of 2 Florentine Gardens, Hillhead Glasgow, Civil
Engineer and Emeritus Professor of Civil Engineering and Mechanics in the
University of Glasgow aforesaid, do hereby derlare the nature of this invention to
be as follows:-
My invention consists primarily of the exchanging of old air for new by means
of a mechanism which with its casing call the exchange wheel. The exchange
wheel has some resemblance to an ordinary fan wheel, but has additional arrange-
ments and capabilities. It has a number of septums or blades radiating out from
its axle to its circumference. Ten or twelve such blades may be suitable and
convenient. The position to be chosen for the wheel may admit of variation
according to circumstances, but to help the imagination the wheel may be regarded
as being placed in an opening like a doorway in a vertical partition separating the
external atmosphere from the air of the house or compartment to be ventilated,
and the axle may be regarded as placed horizontally across the opening. The
wheel revolves within a fixed casing which forms an internal lip to the aperture
and fits closely to the circumference of the wheel at two diametrically opposite
parts, each of them extending through an angular space as great as that comprised
between two of the blades of the wheel, and fits closely also to the two sides of
the wheel along spaces extending radially from these circumferential fitting parts
in to the axle of the wheel or nearly so. The aperture within the lips I call the
portal. The wheel can revolve within this closely surrounding casing without
rubbing on it; and the arrangement is such that whether the wheel be standing
still or revolving the two halves into which the portal is divided by the axle are
Each space
always both closed, each by at least one of the radiating blades.
between one blade and the next may be called a lobe-chamber, or more briefly
may sometimes be referred to simply as a chamber. Now, as the wheel revolves,
each lobe-chamber which passes from without in through one half of the portal
conveys in with it its full of air from the outside; and at the same time and in
like manner, each lobe-chamber which passes from within out through the other
half of the portal conveys out with it its full of air from the inside. Also, every
lobe-chamber which has just passed the portal from without inwards forthwith
discharges its contained air, or a great part thereof, to the inside in virtue of the
centrifugal tendency of that revolving mass of air, and is filled instead with air of
the interior which in like manner it conveys with it in passing out through the
other half of the portal and then throws it off to the external atmosphere while
getting itself filled instead with a supply of external air to be conveyed in through
the portal in the manner before described, and thus to begin another succession
of processes alike with the previous one. In addition to the encasing of the wheel
y the closely fitting lips of the portal as above described, I judge it to be often
advantageous to make extensions of the casing from that portal margin to both
sides inward and outward, so as to form two shoots for guidance of the airs
departing from the circumference of the wheel for the better keeping of the airs
departing from the wheel separate from the airs incoming to it. This wheel expels
air at one side of its axis, and intro luces an approximately equal quantity at the
other side and this takes place notwithstanding the varying forces of the wind
outside of the building. In this the exchange wheel differs essentially from an
or linary revolving fan-propeller, or a screw air propeller. When the exchange

page_text: wheel is left standing still it closes the air passages as closely as convenience in
fitting may permit.
My invention includes also, for cases where desirable, the use of a fan wheel as
a circulation blower for promoting circulation within the enclosed space wanted to
be ventilated or sometimes warmed, but the exchange wheel can itself in some
cases sufficiently promote the internal circulation wanted besides producing the
requisite exchange of old air for new. For the application and distribution of
warmth employ any of the ordinary good heaters such as hot water pipes, steam
pipes, or stoves for applying the heat to the circulating air at some convenient part
of its course. In the application of my invention I further arrange that in this
circulation the fresh incoming air is mixed with a portion of the old air at a place
in the circulation suitable for avoiding discomforts which might otherwise ensue
from alternate draughts or puft's of the old air and new air insufficiently mixed on
the occupants of the room or rooms, or detrement to objects kept or stored in the
apartments; and with a view of preventing the heavy cold air from lodging in the
lower part of the room I make the circulation such as to drain away the cold air
from the floor by apertures there or as low down as may be convenient, and 1
make the circulating air enter the apartment at the ceiling or at some conveniently
elevated place so that the circulation is in the main downward through the
apartment.
I contemplate also as a part of my invention the arrestment in whole or in
part of the exchanging action of the exchange wheel while maintaining the
internal circulation blowing action either of it or of a separate circulation
blowing fan; all this being for occasions when little or no exchanging of air is
requisite but when the interior of the room or rooms or building generally is
wanted to be warned, as for instance in the case of an assembly room or church
during a considerable length of time before assembling of the people to the
building. For such purposes the exchanging action of the exchange wheel may
he arrested or abated by closing wholly or partly the inlets and outlets between
the exchange wheel and the external atmosphere and when desirable it may be
worked at a slower speed or may be stopped, and the circulation blower, if one is
provided, may be kept working.
Dated this 15th day of April 1891.
BOTTOMLEY & LIDDLE,
154, St. Vincent Street, Glasgow, Applicant's Agents.
COMPLETE SPECIFICATION.
Improvements in Ventilation and in Distribution of Warmth by
Movements of Air.
I, JAMES THOMSON, of 2 Florentine Gardens, Hillhead, Glasgow, Civil
Engineer and Emeritus Professor of Civil Engineering and Mechanics in the
University of Glasgow aforesaid 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 consists primarily of the exchanging of old air for new by means
of a mechanism which with its casing I call the ex lang wheel. The exchange
whed has some resemblance to an ordinary fan who but has additional arrange-
nents and capabilities. It has a number of septus or biales radiating out from
its axle to its circumference. Ten
or twelve such dades may be suitable and
convenient. The position to chosen for the wheel may almit of variation
according to circumstances, but to help the imagination the wheel may be
regarded as being placed in an opening like a doorway in a vertical partition
separating the external atmosphere from the air of the house or compartment to
be ventilated, and the axle may be regarded as placed horizontally across the
opening. This aperture I call the portal. The wheel revolves within a fixed

page_text: casing which forms an internal lip to the aperture and fits closely to the circum-
ference of the wheel at two parts diametrically opposite or nearly so, each of
them extending through an angular space as great as that comprised between
two of the blades of the wheel and fits closely also to the two sides of the wheel
along four sector-shaped spaces extending radially from these circumferential fitting
parts in to the axle of the wheel or nearly so. These four sector-shaped fitting
parts of the casing may be named as the sectors, or the side sectors, and the
conjoint fitting parts comprising the cylindrical and sector shaped parts, and already
mentioned as forining an internal lip to the portal aperture may now be called the
portal fittings. The wheel can revolve within this closely surrounding casing
without rubbing on it; and the arrangement is such that whether the wheel be
standing still or revolving the two halves into which the portal is divided by the
axle are always both closed, each by at least one of the radiating blades. Each
space between one blade and the next may be called a lobe-chamber, or more
briefly may sometimes be referred to simply as a chamber. Now, as the wheel
revolves each lobe-chamber which passes from without in through one half of the
portal conveys in with it its full of air from the outside; and at the same time
and in like manner, each lobe-chamber which passes from within out through the
other half of the portal conveys out with it its full of air from the inside. Also
every lobe-chamber which has just passed the portal from without inwards forth-
with discharges its contained air, or a great part thereof, to the inside in virtue of
the centrifugal tendency of that revolving mass of air, and is filled instead with
air of the interior which in like manner it conveys with it in passing out through
the other half of the portal, and then throws that air or a great part thereof
away to the external atinosphere while getting itself filled instead with a supply
of external air to be conveyed in through the portal in the manner before
described; and thereupon begins another succession of processes alike with the
previous one. The wheel with its casing or portal fittings thus described I designate
as the simple exchange wheel.
In addition to the encasing of the wheel by the portal fittings as above described
judge it to be often advantageous to make extensions of the casing from its
edges or margins, or in other words from the edges or margins of the portal fittings
to both sides, inward and outward so as to form two shoots for guidance of the airs
departing from the circumference of the wheel for the better keeping of the airs
departing from the wheel separate from the airs incoming to it. This form of the
exchange wheel with casing thus extended I designate as the exchange wheel with
shoots.
The wheel expels air at one side of its axle, and introduces an approximately
equal quantity at the other side and this takes place notwithstanding the varying
forces of the wind outside of the building. In this the exchange wheel differs
essentially from an ordinary revolving fan-propeller, or a screw air propeller.
When the exchange wheel is left standing still it closes the air passages as closely
as convenience in fitting may permit.
My invention includes also for cases where desirable, the use of a fan wheel as a
circulation-blower for promoting circulation within the enclosed space wanted to
be ventilated or sometimes warmed, but the exchange wheel can itself in some
cases sufficiently promote the internal circulation wanted besides producing the
requi-ite exchange of old air for new. Thus the circulating power of the exchange
wheel with shoots can be increased while its exchanging effect can be kept in
control or entirely stopped, by running the wheel quicker and obstructing the access
of external air to the wheel or the departure of air from the wheel to the external
atmosphere or both.
For the application and distribution of warmth I employ any of the ordinary
good heaters such as hot water pipes, steam pipes or stoves for applying the heat
to the circulating air at some convenient part of its course.
I further arrange
that in this circulation the fresh incoming air is mixed with a portion of the old
air at a place in the circulation suitable for avoiding discomforts which might

page_text: otherwise ensue from alternate draughts or puffs of the old air and new air
insufficiently mixed on the occupants of the room or rooms, or detrement to objects
kept or stored in the apartments.
With a view of preventing the heavy cold air from lodging in the lower part of
the room I make the circulation such as to drain away the cold air from the floor
by apertures there or as low down as may be convenient, and I make the
circulating air enter the apartment at the ceiling or at some conveniently elevated
place, so that the circulation is in the main downward through the apartment.
I contemplate also as a part of my invention the arrestment in whole or in part
of the exchanging action of the exchange wheel while maintaining the internal
circulation-blowing-action either of it or of a separate circulation-blowing-fan: all
this being for occasions when little or no exchanging of air is requisite, but when
the interior of the room or rooms or building generally is wanted to be warmed, a
for instance in the case of an assembly room or church during a considerable
length of time before assembling of the people to the building.
For such purposes the exchanging action of the exchange wheel may be arrested
or abated by closing wholly or partly the inlets and outlets between the exchange
wheel and the external atmosphere; and when desirable it may be worked at a
slower speed or may be stopped and the circulation blower, if one is provided,
may be kept working.
In order that my invention may be properly understood and readily carried into
effect I have hereunto appended an explanatory sheet of drawings in the several
figures of which corresponding parts are marked with the same letters of
reference.
Figure is an illustration of the system of ventilation and distribution of
warmth.
Figure 2 is a side elevation of the exchange wheel stripped of its casing.
Figure 3 shows an end view of the exchange wheel with a sectional view of the
casing where closely fitting round the wheel at the portal and shows also the
partition in section cut through its own medial plane.
The system of ventilation is illustrated by Figure 1, in which the exchange
wheel A is placed in an opening in a vertical partition B separating the external
atmosphere from the air of the house or compartment to be ventilated. The air
in the space surrounding the outer half of the exchange wheel casing is regarded
as external air, because the external atmosphere is freely admitted to that space by
ample openings L. Also the air in the space K surrounding the inner half of the
exchange wheel casing is regarded as house air, that space bcing by means of the
aperture H and ducts leading thereto supplied freely with air from the apartment
to be ventilated, as will be more fully explained further on. In the arrangement
exhibited by the drawings there are two flat circular side-plates d forming portions
of the entire casing, shoots included, there shown. These circular side-plates may
conveniently be made of cast iron with the faces next to the wheel turned true so
that the edges of the blades may pass close to the plates without rubbing as the
wheel revolves. At two diametrically opposite parts these plates are connected by
pieces e which fit closely to the circumference of the wheel and extend ench
through an angular space as great as that comprised between two of the blades of
the wheel. In each of the two circular side-plates d there are two large
apertures g and g', making in all four such apertures. These extend outwards
from the centre and are for the admission of air. The two side apertures gare
for admitting extern air to the revolving wheel, while the two apertures are for
admitting house air to the revolving wheel.
C
The exchange wheel throws house air out through_the_shot C and throws
external air in to the warning chamber D by the shoot E. The construction and
action of the exchange wheel will be more fully understood further on in the
Specification. From the warming chamber D the air passes to the fan F which
I call the circulation blower and which drives the air up the duct G which carries
up so that it may enter the apartment at the ceiling or at some conveniently
it

page_text: elevated places. The air is withdrawn from the floor by apertures there or as low
down as may be convenient and is conveyed thence by a duct or ducts so as to
constitute a circulating current, from which the exchange wheel withdraws a
portion to expel from the building to the outer atmosphere, and into which current
it throws an approximately equal quantity from the external atmosphere. In
Figure 1 the confluence of this incoming extern air with the circulating current
takes place in ordinary working partly within the exchange wheel and partly
within the warming room, the incoming fresh air being, as already explained thrown
into the warming room by the shoot E; while the circulating air with which it is
to unite enters the warming room by any convenient opening or openings repre-
sented by in the figure. From the warming room the circulation current
modified as it is by the exchange and the warming, passes on to the circulation
blower, and thence by the duet G to continue its circuit in the manner before
described. Thus the circulation is in the main downwards through the apartment.
Sliding or hinged shutters may be provided for the inlet openings 1 and for the
outlet of the shoot C which can be brought into use to close wholly or partly the
inlet and outlet between the exchange wheel and the external atmosphere
when little or no exchange of air is required but when the interior of the room or
roons or building generally is wanted to be warmed.
In case of the exchange wheel being made to serve for promoting the internal
circulation without the help of the cirenlation blower already described no
aperture such as shown at I in the figure should be introduced because any such
aperture would allow the air or a part thereof which ought to circulate through
the apartment to take a short circuit from the shoot E through the aperture I, and
thence by the aperturo H back to the side orifices g without going through the
apartment.
The two circular side-plates d include virtually the four sectors of what has been
called the portal fittings, together with four other pieces of sector shape lessened
by the four side openings. These last four sector like pieces together with the
protruding shoot pieces CC and EE go together to complete the shoots already
mentioned as extending from the margins of the portal fittings. If these complete
shoots were removed the remainder would be that which has been already clearly
described under the name of the simple exchange wheel.
do not confine myself to the two forms of exchange wheel-the simple
exchange wheel and the one with two shoots. The exchange wheel might in some
cases serve well with only one shoot. Thus in case of the wheel on one side of
the portal having to receive its air at less pressure than that at which on the same
side of the portal the air departing from its circumference has to be driven off, the
hoot would be requisite for the side where the propulsion is resisted while at the
side of the portal where there is little or no resistance the shoot might be dispensed
with. Such resistance as is here referred to it may be understood would present
itself to the action of the wheel on the house side of the portal in case of the
wheel having to propel the circulation air through long ducts, rather much limited
as to their cross sectional area, without the aid of a separate circulation blower and
in other like cases.
The exchange wheel when made with a single shoot or with two shoots I call the
shoot exchange wheel.
The simple exchange wheel, it is to be noticed, is not suitable for promoting
circulation through ducts but may be used in company with a separate circula-
tion blower.
For the warming appliances I do not confine myself to the particular situation
chosen in the arrangement exhibited in the drawing, Figure 1; but such appliances
may be introduced at any convenient and suitable part or parts of the whole
circuit.
The revolving exchange wheel A has septums or blades a extending from the
axle to the circumference. These blades may be straight or curved. In the
illustration they are straight, but if curved some slight alterations obvious enough

page_text: would have to be made in the casing to adapt it to their form. A curved form
might possibly present some advantages towards attainment of stiffness combined
with lightness or for other reasons in some instances. A circular plate bis attached
to the axle e to which the blades can be securely fixed by rivets or otherwise.
Each space between one blade and the next forms a chamber marked, etc.
As the wheel revolves each chamber, which passes from without in through one
half of the portal, conveys in with it its full of external air, and as it passes to the
snecessive positions, it gradually discharges by centrifugal action
this air into the shoot while it draws in through the openings g house air, and by
the time it arrives at the position in the lower half of the portal it is filled
mainly with house air. As it passes through the successive positionsƒƒ“ƒ”
ir discharges the house air into the shoot (and draws in external air through the
two side openings so that when it again arrives at the position fit is mainly
filled with external air. Thus as the wheel revolves there is a constant interchange
of external air and house air.
10
The axle of the wheel it is to be understood is to turn in suitably arranged
bearings which may be of any of the ordinary kinds such as ordinary mechanicians
are well enough familiar with. These should be placed so as to give sufficient
support and steadying to the axle without injuriously obstructing the access of the
air to the inflow orifices in the circular side plates of the casing. To help the
imagination as to good arrangements for making room for the axle while having its
centre-line or axis in or near the medial plane of the partition, as for convenience
may be desirable, there may be kept open in the partition a slit for the reception of
the axle, and this slit may be closed by affixing a channel piece extending half
round the shaft and connecting the two parts of the partition where separated by
the slit in such manner as is indicated by Figure 4.
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 1
claim is :-
1. The system of ventilation and distribution of warmth described in the fore-
going explanations and illustrated by the accompanying sheet of drawings
consisting of the exchange wheel, warming appliances and ducts together with the
circulation blower in some cases and without it in others by means of which
external air is exchanged for house air and a circulation of the air is promoted and
warmth is distributed through the house or apartment by the movements of the
air; and motion mainly from above downward in the apartment is produced.
2. The shoot exchange wheel for use in ventilation by producing exchange of
air and promoting circulation through ducts.
3. The simple exchange wheel in accompaniment with a circulation blower, for
use jointly in ventilation for producing exchange of air and promoting circulation
through ducts.
Dated this 13th day of February 1892.
BOTTOMLEY & LIDDLE,
154, St. Vincent Street, Glasgow, Applicant's Agents.