IMPROVEMENTS IN APPARATUS FOR WITHDRAWING OR FORCING AIR FOR VENTILATING AND OTHER PURPOSES."
Year: 1880

page_text: LETTERS PATENT to William Verity and Benjamin Verity, both of Stanhope
Street, Euston Road, in the County of Middlesex, for an Invention of
"IMPROVEMENTS IN APPARATUS FOR WITHDRAWING OR FORCING AIR FOR
VENTILATING AND OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said William Verity and Benjamin
Verity at the Office of the Commissioners of Patents on the 15th December
1880.
WILLIAM VERITY and BENJAMIN VERITY, both of Stanhope Street, Euston Road,
in the County of Middlesex. "IMPROVEMENTS IN APPARATUS FOR WITHDRAWING
OR FORCING AIR FOR VENTILATING AND OTHER PURPOSES."
At the present time revolving fans are for the most part used for producing currents
of air. The fans are formed of an axis having radial blades projecting from it; the
blades are enclosed in a circular casing with closed ends, and from which there is a
tangential outlet. An inlet is formed at the centre of one or both of the ends of
the casing for air to enter. When the axis is revolved air is drawn in at this central
opening, and is driven outwards by the radial blades, and forced away through the
tangential outlet. We have found that the action of such apparatus can be
greatly improved by surrounding the central inlet opening with a cylinder
projecting outwards from the end of the casing parallel with the axis, and by
securing to the axis or to the fan blades a screw blade or blades, such screw
blade or blades being contained within the cylinder, the cylinder is open at its
end, and also, if desired, an opening may be formed on one side of it for air to
enter. By this means when the axis of the fan is revolved, the screw blade or
blades will draw air inwards through the cylinder, and deliver it into the centre of
the fan casing, and will so constantly keep up a supply of air to the centre of the
fan whilst the fan blades force the air outwards and away through the tangential
outlet. By this means the volume of air delivered by a fan may be greatly
Duins 21

page_text: increased without the expenditure of more driving power. An inlet cylinder and
screw blades may thus be applied at one end only of the cylinder, or a screw and
inlet cylinder might be applied at both ends.
The casing of the fan may also be made with numerous outlet openings instead
of with a single outlet only.
In some cases, and especially when the fan is driven by a small jet of water
directed against the corrugated circumference of a wheel which is fixed on the fan
axis, we mount the fan axis in a vertical position, and with the corrugated wheel
either above or below the fan and screw blades. The lower end of the axis is
passed down through a loosely fitting stuffing box into a closed vessel filled with
oil, and a cone point at the bottom of the vessel enters a corresponding hollow in
the end of the axis, the upper end of the axis is pointed and enters a corresponding
recess at the bottom of a closed vessel filled with oil. This oil vessel is mounted in
vertical guides in the frame of the apparatus, so that it can be raised or lowered. A
fine hole is made from the bottom of the recess into the oil vessel, and the oil vessel
is either allowed to rest by its own weight on the top of the spindle, or is pressed
downwards on to it by a spring.
In this way when a minute quantity of oil has passed down through the fine hole
and come between the coned surfaces of the spindle and oil vessel, the entrance of
air into the oil vessl is closed, and no further oil descends until the oil between the
coned surfaces has escaped sufficiently to allow a minute quantity of air again to
enter the oil vessel.
By supporting the axis of the fan in the above manner, it can be turned with
but little friction, and will run for a great length of time without attention or the
addition of any oil for lubrication.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Verity and Benjamin Verity in the Great Seal Patent
Office on the 15th June 1881.
WILLIAM VERITY and Benjamin VERITY, both of Stanhope Street, Euston Road,
in the County of Middlesex. "IMPROVEMENTS IN APPARATUS FOR WITHDRAWING
OR FORCING AIR FOR VENTILATING AND OTHER PURPOSES."
+
At the present time revolving fans are for the most part used for producing
currents of air. The fans are formed of an axis having radial blades projecting
from it; the blades are enclosed in a circular casing with closed ends, and from
which there is a tangential outlet. An inlet is formed at the centre of one or
both of the ends of the casing for air to enter. When the axis is revolved, air is
drawn in at this central opening, and is driven outwards by the radial blades, and
forced away through the tangential outlet. We have found that the action of
such apparatus can be greatly improved by surrounding the central inlet opening
with a cylinder projecting outwards from the end of the casing, parallel with the
axis, and by securing to the axis or to the fan blades a screw blade or blades, such
screw blade or blades being contained within the cylinder. The cylinder is open
at its end, and also if desired an opening may be formed on one side of it for air
to enter. By this means when the axis of the fan is revolved the screw blade or
blades will draw air inwards through the cylinder and deliver it into the centre of
the fan casing, and will so constantly keep up a supply of air to the centre of the
fan, whilst the fan blades force the air outwards and away through the tangential
outlet.
By this means the volume of air delivered by a fan may be greatly increased
without the expenditure of more driving power.
An inlet cylinder and screw blades may thus be applied at one end only of the
cylinder, or a screw and inlet cylinder might be applied at both ends.
The casing of the fan may also be made with numerous outlet openings instead
of with a single outlet only.
In some cases, and especially when the fan is driven by a small jet of water
directed against the corrugated circumference of a wheel which is fixed on the fan
axis, we mount the fan axis in a vertical position, and with the corrugated wheels
either above or below the fan and screw blades. The lower end of the axis is
passed down through a loosely fitting stuffing box into a closed vessel filled with
oil, and a cone point at the bottom of the vessel enters a corresponding hollow
in the end of the axis. The upper end of the axis is pointed and enters a
corresponding recess at the bottom of a closed vessel filled with oil. This oil vessel
is mounted in vertical guides in the frame of the apparatus, so that it can be raised
or lowered.
A fine hole is made from the bottom of the recess into the oil vessel, and the oil
vessel is either allowed to rest by its own weight on the top of the spindle, or is
pressed downwards on to it by a spring.
In this way when a minute quantity of oil has passed down through the fine hole,
and come between the coned surfaces of the spindle and oil vessel, the entrance of air
into the oil vessel is closed, and no further oil descends until the oil between the
coned surfaces has escaped sufficiently to allow a minute quantity of air again to
enter the oil vessel.
By supporting the axis of the fan in the above manner it can be turned with but
little friction, and will run for a great length of time without attention or the
addition of any oil for lubrication.

page_text: In the Drawings hereunto annexed we have shown examples of apparatus in
which the above described improvements are embodied.
Figure 1 shows a vertical section of one form of the apparatus in which the fan
is revolved by means of a small jet or jets of water directed against the periphery
of a toothed wheel which is fixed on the fan axis. Figure 2 is a horizontal section
of the same taken through the radial fan blades, and Figure 3 is a horizontal section
taken through the toothed wheel against which the jets of water are caused to
impinge.
A is the fixed outer casing; B is the axis carrying the radial fan blades C;
D, D, are screw blades fixed to the axis below the radial blades C; E, E, is the
fixed cylindrical casing surrounding the screw blades; F is an opening at one side
of this casing through which air can pass to the screw blades; G is the toothed
wheel against which thin streams of water are directed from the jets H. Water is
supplied to these jets from an elevated cistern or from a water main. When thin
streams of water from the jets H are caused to impinge against the toothed wheel G,
this wheel is caused to revolve, and turns the axis B with it, the screw blades then
force a stream of air upwards through the cylindrical casing E into the centre of
the chamber of the fixed case which surrounds the fan blades. The air so supplied
to the centre of the casing is by the action of the radial fan blades forced outwards
away from the axis and passes away by the tangential outlet I. The lower end of
the axis B rests upon a fixed cone point K at the botom of an oil vessel L. The
axis passes down through a hole in the centre of the cover of this vessel, and
through a hole in a disc of felt carried by the cover, this serves to exclude dust
from the oil vessel without putting any material amount of friction upon the axis.
The upper end of the axis B is formed to a cone point; this enters a corresponding
recess in the bottom of an oil vessel M. N is a fine hole passing from the interior
of the oil vessel to the cone recess at its bottom. The oil vessel M can move up
and down in vertical guides O and rests upon the cone point, on the top of the
axis B, and so forms a bearing for the upper end of this axis; or in place of the
oil vessel being made so that it can move up and down in vertical guides, it might
be carried by a long hinge joint, as shown at Figure 3*. P is a small stuffing box
through which the axis B passes, and which serves to shut off communication
between the chamber of the casing which surrounds the water wheel G and the
chamber which surrounds the fan.
Figures 4 and 5 show apparatus similar in its action to that shown at Figures 1,
2, and 3, except that the fan axis, in place of being revolved by water jets acting
upon the circumference of a toothed wheel, is revolved by the action of the wind
upon a cup wheel fixed upon the axis; Figure is a vertical section of the
apparatus, and Figure 5 a plan view.
A is the fixed outer casing; B is the fan axis; C, C, are the radial blades of the
fan; D, D, are the screw blades; E is a fixed cylindrical casing surrounding the
screw blades. The air to be drawn off from any room or part of a building is
conducted by a suitable pipe or channel to the lower end F of the casing E; G is a
cup wheel on the axis B; this wheel is formed, as shown in the Drawing, in a
similar manner to the cup wheels used for measuring the velocity of currents of
wind, and revolves whenever a current of wind blows past it.
Whenever the cup wheel revolves, the axis B turns with it, and the screw
blades D force up air to the fan blades, and the fan blades force the air outwards
away from the axis, and it passes away through the numerous outlet openings I
which are formed around the circumference of the outer casing A, as shown.
The lower end of the axis B rests on a point at the bottom of an oil cup L, and
the upper end is supported in a bearing which is surrounded by an oil vessel M
carried by the axis B as shown, or it might be supported in other suitable manner.
O is an opening on the top of the axis B, closed air tight by a screw plug.
Whenever the upper bearing of the axis requires a fresh supply of oil for lubrication
the screw plug may be unscrewed, and a small quantity of oil poured into it, the

page_text: oil will run down into the bearing and will be prevented from escaping from it by
the oil cup M which is fixed to the axis and which surrounds the bearing.
We claim,―
First. The construction of centrifugal fans with a screw blade or blades to
propel a current of air into the centre of the fan, and so facilitate the projection of
the air outwards from the axis of the fan by the action of the fan blades,
substantially as described..
Second. The construction of the upper bearing of the spindle, of revolving fans
at bottom of an oil vessel which is pressed downwards on to the spindle, either by
its own weight or by a spring, and with a fine hole leading from the oil vessel into
the bearing to supply oil to it, whilst the too free escape of oil from the oil vessel
through this hole is prevented by the end of the spindle, as hereinbefore described.
In witness whereof, I, the said Benjamin Verity, have hereunto set my
hand and seal, this Tenth day of June, in the year of our Lord One
thousand eight hundred and eighty one.