An Improved Ventilating Fan and Steam Engine for Actuating the same.
Year: 1893

page_text: Date of Application, 14th Jan., 1893
Complete Specification Left, 14th Oct., 1893-Accepted, 13th Jan., 1894
PROVISIONAL SPECIFICATION.
An Improved Ventilating Fan and Steam Engine for Actuating
the same.
I, JOHN DUNCAN GRAY THOMPSON, Ventilating and Consulting Engineer,
159 Queen Victoria Street, London, E.C. do hereby declare the nature of my
invention to be as follows:-
This invention has reference to and comprises a new or improved construction of
exhaust fan or pressure blower and engine or motor to be used in combination there-
with, for the ventilating of buildings, ships, and other structures or vessels, in a
more complete and efficient manner than hitherto.
The fan would consist of a series of blades attached by rivets to radial bars or
arms adjustably secured to a central hub mounted on a rotating shaft carried in
adjustable bearings, the whole being covered in by a protecting wire gauze or other
frame.
By my improvements the fan blades are formed of great breadth from their outer
extremity to past their centre where their convex edges gradually come in with a
gentle curve on each side and then approach outwards to a straight base line at
inner extremity. These blades are also curved inwards transversely on one half
their breadth, all so as to carry or generate a maximum quantity or intensity of air
in their rotating motion. The radial bars or arms to which the fan blades are
attached would have their inner ends screwed into the hub on the rotating shaft, so
as to be capable of adjustment to any desired angle, or be reversed for use either
as an exhaust fan or as a pressure blower.
The central fan sbaft would be connected to the engine shaft by a clutch or other
coupling. The engine frame would consist of a cylindrical box casing made in two
main removable parts bolted together and having the driving shaft mounted in
adjustable bearings at its ends, said bearings consisting of an outer cast metal box,
an inner brass bearing and metal packing ring, a brass bearing tapering on upper
surface towards outer end, and an intermediate brass tubular piece mounted over
this, tapered on inner surface in the reverse direction to the former parts outer
surface, and screwed into the cast metal box part on outer surface. The shaft is
formed with a central hole and has mounted on it a lubricator at the top end from
which the lubricant is made to flow through the central hole and through apertures
to the different bearings. Two cylinders are formed in the frame-work in the
same straight line in which work trunk pistons connected by rods to cranks set at
right angles on the central driving shaft. A steam chest casing is fitted over one
of these cylinders and is formed with inlet and exhaust steam ports over which
work a slide valve connected by a rod, passing through fluid tight bearings, to
an eccentric mounted on the driving shaft of the engine. A pipe also leads steam
from this steam chest to a port on the closed end of the other cylinder, and the
slide valve is so set and arranged that one of these single steam acting pistons is on
its outstroke while the other is on its instroke, so as to obtain a maximum
continuous power in driving the fan. By unscrewing the securing bolts one part of
the frame can be removed and free access got to the cylinders, pistons, cranks and
eccentric for renewal or repair.
Dated the 12th Jan 1802
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.

page_text: .
An Improved Ventilating Fan and Steam Engine for Actuating
the same.
I, JOHN DUNCAN GRAY THOMPSON, Ventilating and Consulting Engineer,
159 Queen Victoria Street, London, E.C. do hereby declare the nature of my
invention, and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement in writing, that is
to say :-
This invention has reference to a new or improved construction of exhaust fan
or pressure blower, and engine or motor to be used in combination therewith, for
ventilation and like purposes such as cooling, heating, drying and the like in
buildings, ships, and other structures or vessels in a more complete and efficient
manner than hitherto.
And in order that my said invention and the manner of performing or carrying
the same into effect or practice may be properly understood, I have hereunto
appended two explanatory sheets of drawings, in which the same reference letters
are used to indicate corresponding parts in all the figures where shown.
Figures 1 and 2 are an elevation and plan view respectively showing one
arrangement of my improved exhaust fan or pressure blower as carried on a wall
bracket frame.
Figures 3 and 4 are elevations at right angles to each other showing another
arrangement of my improved fan as carried on a base frame. While
Figure 5 is an elevation showing the fan as coupled to and driven direct by a
steam engine.
Figures 6, 7, and 8 show edge views of three modified forms of the shape of
fan blades.
And
Figure 9 on Sheet 2 shows a sectional elevation of my improved construction of
engine.
Referring to these drawings:-The fan would consist of a series of blades a
attached by rivets or otherwise to radial bars or arms b adjustably secured to a
central hub B, mounted on a rotating shaft C, carried in adjustable bearings, the
whole being covered in by a protecting wire gauze or other frame.
By my improvements the fan blades a are formed of great breadth from their
outer extremity a' to past their centre where their convex edges a² gradually come
in with a gentle curve on each side at a¹ and then approach outwards to a straight
base line at inner extremity a³. These blades would preferably be embossed
at a', and may curve inwards transversely on one half their breadth, as shown in
Figures 2 and 6, or may gradually curve all the length as in Figure 7, or they
may assume a straight course, as in Figure 8, all so as to carry or generate a
maximum quantity or intensity of air in their rotating motion. The fan blades a
would be riveted or attached to radial bars b either with single outer arms b', as
in Figure 1, or with double curved wings as in Figure 3, aud would have their inner
ends screwed into the hub B, on the rotating shaft C, and tightened up by nuts 6,
so as to be capable of adjustment to any desired angle, or be reversed for use
either as an exhaust fan or as a pressure blower, according as desired.
In the arrangement of fan, as shown in Figures 1 and 2 the frame which encloses
it consists of a cast iron or other rim D bolted to wall through holes at D³, and
three curved bracket arms D' bolted at B' to seginental malleable iron or other
plates at the centre; and the shaft C is carried in bearings at D2 D"; tightening
up collars C¹ being placed on shaft C between inner bearing D", and the boss B of
fan. The fan shaft C would be driven by a belt passed over a pulley C³ from any
prime moving shaft.
In the arrangement shown in Figures 3 and 4 the fan would be carried on a sole

page_text: frame D. The shaft C carrying the boss B, and fan blade a is carried in hollow
octagonal bearings D, D", on each side of frame, and is adjusted by a series of
pinching screws d. The outer rim frame D would preferably be formed of sheet
ron and a series of radial screw bars D', would securely stay this to the central
bearings D, and sole, frame D'. The shaft C would be driven from the overhung
pulley C², and in other respects this arrangement would be substantially the same
as that shown in Figures 1 and 2.
In the arrangement shown in Figure 5 the fan shaft C is shown as connected by
a clutch or other coupling C³ to the shaft E' of an engine E, or other motor.
Referring to Figure 9 on Sheet 2 :-The engine frame would consist of a
cylindrical box casing made in two main removable parts A, A' bolted together and
having the driving shaft B mounted in adjustable bearings at its ends, said bearing
consisting of an outer cast metal stuffing box a, an inner brass bearing al and metal
packing ring all and an end gland a² extending into metal packing a" and secured
by studs a from stuffing box flange a fitted through flange on outer end of gland a²
and tightened up by nuts. The shaft B is formed with a central hole band has
mounted on it a lubricator at the top end from which the lubricant is made to flow
through the central hole 6 and through apertures to the different bearings. Two
cylinders C, C', are formed in the frame-work in the same straight line in which
work trunk pistons c, c', connected by rods c², c³, to and actuating a crank con
the central driving shaft B. A steam chest casing D is fitted over one of these
cylinders C and is formed with inlet and exhaust steam ports d, d', over which work
a slide valve D¹ connected by a rod D³, passing through fluid tight bearings D", to
an eccentric D³ mounted on the driving shaft B of the engine. A pipe D*, or it
may be a casing or trunk leads the steam from this steam chest D to a port d' on
the closed end of the other cylinder C¹, and the slide valve D³, is so set and
arranged as to supply steam to one of these single steam acting pistons c or c¹ on its
outstroke while the other is on its instroke, so as to obtain a maximum continuous
power in driving the fan. By unscrewing the securing bolts one part A of the
frame can be removed and free access got to the cylinders, pistons, cranks and
eccentric for removal or repair.
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. The construction of the blades of fans in the improved manner herein
described in reference to and shown in the accompanying drawings.
Second. The arrangement and combination of the parts of the improved fans
with their carrying frames and adjustable fittings, substantially as and for the
purposes herein described in reference to and shown in the accompanying drawings.
Third. In combination with a fan the improved construction of steam engine
herein described in reference to and shown in the accompanying drawings.
Fourth. In combination with a fan the arrangement of slide valve and casing for
supplying steam to both cylinders of engine, substantially as herein described in
reference to and shown in the accompanying drawings.
Dated the 13th October 1893.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.